The 'Campaign for Burma' was fought between Japanese (and allied) and a combination of British (essentially imperial), Chinese and US forces in the British colony of Burma (14 December 1941/13 September 1945).
Burma was part of the South-East Asian theatre of World War II and primarily involved forces of the Allies (mainly from the British empire and China, with US support) against the invading Japanese forces, which were supported by the Thai Phayap Army, as well as two collaborationist independence movements and armies. The first of these was the Burma Independence Army, which spearheaded the initial attacks against the country. The Indian National Army, led by Subhas Chandra Bose of the Free India movement, also collaborated with the Japanese forces, especially during the 'U' operation of 1944. Nominally independent puppet states were established in the conquered areas and some territories were annexed by Thailand. In 1942 and 1943, the Allied forces in British India launched several failed offensives to retake lost territories. Fighting intensified in 1944, and British empire forces peaked at around 1 million men in land and air forces. These forces were drawn primarily from British India, with British Army forces (equivalent to eight regular infantry divisions and six tank regiments), 100,000 East African and West African colonial troops, and smaller numbers of land and air forces from several other colonies. These additional forces allowed the Allied recapture of Burma in 1945.
The campaign had a number of notable features. The geographical characteristics of the region meant that weather, disease and terrain played major roles in operations. The lack of transport infrastructure placed an emphasis on military engineering and air transport to move and supply troops, and to evacuate the wounded. The campaign was also politically complex, with the UK, China and the USA each working toward different strategic priorities. It was also the only land campaign by the Western Allies in the Pacific theatre which proceeded continuously from the start of hostilities to the end of the war, largely as a result of the theatre’s geographical location. By extending from South-East Asia to India, the theatre’s area included some areas which the British lost at the outset of the war, but also included areas of India in which the Japanese advance was eventually brought to a halt and then driven back. The region’s climate is dominated by the seasonal monsoon rains, which allowed effective campaigning for only slightly more than half of each year. This, together with other factors such as famine and disorder in British India, and the priority given by the Allies to the defeat of Germany, prolonged the campaign and divided it into four phases: firstly, the Japanese invasion, which led to the expulsion of British, Indian and Chinese forces in 1942; secondly, failed attempts by the Allies to mount offensives into Burma, from late 1942 to early 1944; thirdly, the 1944 Japanese invasion of India, which ultimately failed following the 'Battle of Kohima' and the 'Battle of Imphal'; and fourthly, the successful Allied offensive which liberated Burma in the period between late 1944 and the middle of 1945.
The campaign was also strongly affected by the political atmosphere which emerged within the South-East Asian regions occupied by Japan, which pursued the Pan-Asianist policy of a 'Greater East Asia Co-Prosperity Sphere'. This paved the way to the emergence of a Japanese-sponsored revolution during the initial invasion and the establishment of the State of Burma, in which the Provisional Government of Free India, with its Indian National Army, was headquartered. The dominating attitude of the Japanese militarists who commanded the Japanese forces stationed in the country, which ultimately doomed the concept of the co-prosperity sphere as a whole, led to local hopes for real independence fade and the war-established Burma National Army revolted against the Japanese in 1945. On the Allied side, political relations were mixed for much of the war. The China-Burma-India Theater, in which the US-trained Chinese 'X' Force operated, led to co-operation between the two countries, but the clash between the strategy proposed by Lieutenant General Joseph W. Stilwell and that of Generalissimo Chiang Kai-shek eventually led to Stilwell’s removal from his position as the US commander of the theatre. On the other hand, relations between India and China were positive as a result of the co-operative Burma Road, built to reach the Chinese 'Y' Force and the Chinese war effort inside China, and the US 'Hump' air effort to carry large quantities of matériel by air over the very difficult eastern end of the Himalayan mountains to China.
The Japanese objectives in the invasion of Burma were initially limited to the capture of Rangoon, the capital and principal sea port. The seizure of Rangoon, the Japanese believed, would close the overland supply line to China and provide a strategic bulwark to defend Japanese gains in British Malaya and the Netherlands East Indies. Lieutenant General Shojiro Iida’s 15th Army, initially comprising just two infantry divisions, moved into northern Thailand, which had signed a treaty of friendship with Japan, and launched an attack over jungle-clad mountain ranges into the southern Burmese province of Tenasserim in January 1942.
In the face of the Japanese advances, very large numbers of Indians, Anglo-Indians and Anglo-Burmese fled Burma. This exodus of about 600,000 persons had, by the autumn of 1942 became possibly the largest mass migration in history. As many as 80,000 of those fleeing died of starvation, exhaustion and disease, and some of the worst massacres in Burma during World War II were perpetrated not by the Japanese but by Burmese gangs linked to the Burma Independence Army.
The Japanese successfully attacked over the Kawkareik pass and captured the port of Moulmein at the mouth of the Salween river after overcoming stiff resistance. They then advanced to the north, outflanking successive British defensive positions. Troops of Major General J. G. Smyth’s Indian 17th Division tried to retreat over the Sittaung river, but Japanese parties reached the vital bridge before they did, and on 22 February, the bridge was demolished to prevent its capture, a decision that has since been extremely contentious.
The consequent loss of two brigades of Indian 17th Division meant that Rangoon could not be defended. General Sir Archibald Wavell, commander-in-chief in India and the head of the American-British-Dutch-Australian Command, nevertheless ordered Rangoon to be held as he was expecting substantial reinforcements from the Middle East. Although some units arrived, counterattacks failed and the new commander of the Burma Army, General the Hon. Sir Harold Alexander, ordered the city to be evacuated on 7 March after its port and oil refinery had been destroyed. The remnants of Burma Army broke out to the north, narrowly escaping encirclement.
On the eastern part of the front, in the 'Battle of Yunnan-Burma Road', Major General Dai An-lan’s Chinese 200th Division held the Japanese for a time around Toungoo, but after the fall of Toungoo the road was open for motorised troops of Lieutenant General Hiroshi Takeuchi’s Japanese 56th Division to shatter the Chinese 6th Army to the east in the Karenni States and advance to the north through the Shan States to capture Lashio, outflanking the Allied defensive lines and isolating the Chinese armies from Yunnan. With the effective collapse of the entire defensive line, there was little option left to the Allied forces but an overland retreat to India or to Yunnan.
After the fall of Rangoon in March 1942, the Allies attempted to make a stand in Upper Burma (the north of the country) after being reinforced by a Chinese Expeditionary Force. The Japanese had also been reinforced by two divisions made available by the capture of Singapore and defeated both Lieutenant General W. J. Slim’s newly organised Burma Corps and the Chinese force. The Allies were also faced with growing numbers of Burmese insurgents, and the civil administration broke down in the areas they still held. With their forces cut off from almost all sources of supply, the Allied commanders finally decided to evacuate their forces from Burma. On 16 April, 7,000 British soldiers were encircled by Lieutenant General Shozo Sakurai’s 33rd Division during the 'Battle of Yenangyaung' and rescued by the Chinese 38th Division.
The retreat was conducted under extremely difficult circumstances. Starving refugees, disorganised stragglers, and the sick and wounded clogged the primitive roads and tracks leading to India. Burma Corps managed to make it most of the way to Imphal, in Manipur in India, just before the monsoon broke in May 1942, having lost most of its equipment and transport. There, the men of the corps found themselves living in the open under torrential rains in extremely unhealthy circumstances. The army and civil authorities in India were very slow to respond to the needs of both the troops and the civilian refugees.
For lack of communication, as the British retreated from Burma, almost none of the Chinese knew about the retreat. Realising that they could not win without British support, some of the 'X' Force committed by Chiang Kai-shek made a hasty and disorganised retreat to India, where they were put under the command of Stilwell, who was Chiang’s chief-of-staff as well as commander of the China-Burma-India Theater. After recuperating, the Chinese were re-equipped and retrained by US instructors. The rest of the Chinese troops tried to return to Yunnan through remote mountainous forests and of these at least half died.
In accordance with their military alliance with Japan signed on 21 December 1941, on 21 March the Thais agreed with the Japanese that the Karenni State and Shan States should be under Thai control, with the rest of Burma under Japanese control.
The leading elements of Thailand’s Phayap Army under General Jarun Rattanakuln Seriroengrit crossed the border into the Shan States on 10 May 1942. Three Thai infantry divisions and one cavalry division, spearheaded by armoured reconnaissance groups and supported by the Royal Thai air force, engaged the retreating Chinese 93rd Division. Kengtung, the Thais' primary objective, was captured on 27 May., and on 12 July, General Phin Choonhavan, who would become the Thai military governor of the occupied Shan State later in the war, ordered the 3rd Division of the Phayap Army from the southern part of the Shan State to occupy Karenni State and expel the Chinese 55th Division from Loikaw. The Chinese troops could not retreat because the routes to Yunnan were controlled by Japanese and Thai forces, and many Chinese soldiers were taken prisoner. The Thais remained in control of the Shan States for the remainder of the war. Their troops suffered from supply shortages and disease, but were not subjected to Allied attacks.
The Japanese did not renew their offensive after the monsoon’s end. They installed a nominally independent Burmese government under Ba Maw, and reformed the Burma Independence Army on a more regular basis as the Burma National Army under General Aung San. In practice, both government and army were strictly controlled by the Japanese authorities.
On the Allied side, operations in Burma over the remainder of 1942 and in 1943 were a study of military frustration. The UK could maintain only three active campaigns, and immediate offensives in both the Middle East and Far East proved impossible for lack of resources. The Middle East was accorded priority, being closer to home and in accordance with the 'Germany First' policy agreed by London and Washington.
The Allied build-up was also hampered by the disordered state of eastern India at the time. There were violent Quit India protests in Bengal and Bihar, which required large numbers of British troops for suppression. There was also a disastrous famine in Bengal, which may have led to 3 million deaths as a result of starvation, disease and exposure. In such conditions of chaos, it was difficult to improve the inadequate lines of communication to the front line in Assam or to make use of local industries for the war effort. Efforts to improve the training of Allied troops took time and in forward areas poor morale and endemic disease combined to reduce the strength and effectiveness of fighting units.
Nevertheless, the Allies mounted two operations during the 1942/43 dry season. The first was the small 'Cannibal' offensive into the Arakan coastal province of Burma. The Indian Eastern Army intended to reoccupy the Mayu peninsula and Akyab island, which had an important airfield. Attacking from Cox’s Bazaar, Major General W. L. Lloyd’s Indian 14th Division advanced to Donbaik, only a few miles from the end of the peninsula, but was halted by a small but well entrenched Japanese force. At this stage of the war, the Allies lacked the means and tactical ability to overcome strongly constructed Japanese bunkers. Repeated British and Indian attacks failed with heavy casualties. Japanese reinforcements arrived from central Burma and, crossing rivers and mountain ranges which the British had declared to be impassable, hit the Indian 14th Division’s exposed left flank and overran several units. The exhausted British were unable to hold any defensive lines and were forced to abandon much equipment and fall back almost to the Indian frontier.
The second action was controversial. Under the command of Brigadier O. C. Wingate, a long-range penetration unit known as the 'Chindits' infiltrated through the Japanese front lines and marched deep into Burma, with the initial aim of cutting the main north/south railway in Burma in an operation codenamed 'Longcloth'. Some 3,000 men entered Burma in many columns. They damaged communications of the Japanese in northern Burma, cutting the railway for possibly two weeks, but suffered heavy casualties to the conditions and disease as much as to the Japanese. Though the results were questioned, the operation was used to propaganda effect, particularly to insist that British and Indian soldiers could live, move and fight as effectively as the Japanese in the jungle, doing much to restore morale among Allied troops.
From December 1943 to November 1944 the strategic balance of the Burma campaign shifted decisively to the Allies. Improvements in Allied leadership, training and logistics, together with greater firepower and growing Allied air superiority, gave the Allied forces a confidence they had previously lacked. In Arakan, Lieutenant General A. F. P. Christison’s XV Indian Corps withstood, and then broke, a Japanese counter-offensive, while the Japanese invasion of India resulted in unbearably heavy losses and the ejection of the Japanese back behind the Chindwin river.
In August 1943, the Allies created the South-East Asia Command as a new combined command responsible for the South-East Asian theatre, under Admiral the Lord Louis Mountbatten. The training, equipment, health and morale of Allied troops under Slim’s British 14th Army was improving swiftly and radically, as was the capacity of the lines of communication in north-eastern India. An innovation was the extensive use of aircraft to transport and supply troops.
The South-East Asia Command had to accommodate several rival plans, many of which had to be dropped for lack of resources. Amphibious landings in the Japanese-occupied Andaman islands group ('Pigstick') and in Arakan were abandoned when the landing craft assigned were recalled to Europe in preparation for the 'Neptune' (iii) landings which paved the way for the 'Overlord' campaign in Normandy.
The major effort was intended to be made by US-trained Chinese troops of Stilwell’s Northern Combat Area Command, to cover the construction of the Ledo Road. Wingate had controversially gained approval for a greatly expanded 'Chindit' force, which was given the task of assisting Stilwell by disrupting the Japanese lines of supply to the northern front. Chiang Kai-shek had also agreed reluctantly to mount an offensive from Yunnan. Under the 14th Army, the Indian XV Corps prepared to renew the advance in Arakan, while Lieutenant General G. A. P. Scooone’s Indian IV Corps launched a tentative advance from Imphal in the centre of the long front to distract Japanese attention from the other offensives.
About the same time that the South-East Asia Command was established, the Japanese created the Burma Area Army under the command of Lieutenant General Masakazu Kawabe, which took under command the 15th Army and Lieutenant General Shozo Sakurai’s newly formed 28th Army. Mutaguchi, the new commander of the 15th Army, wished to mount an offensive against India. The Burma Area Army originally quashed this idea, but found that its superiors at the headquarters of the Southern Expeditionary Army Group in Singapore were more taken with the concept. When the staff at the Southern Expeditionary Army Group was persuaded that the plan was inherently risky, it in turn found that Imperial General Headquarters in Tokyo was in favour of Mutaguchi’s plan.
The Japanese were influenced to an unknown degree by Subhas Chandra Bose, commander of the Indian National Army. This was composed largely of Indian soldiers who had been captured in Malaya or Singapore, and Indians (Tamils) living in Malaya. At Bose’s instigation, a substantial contingent of the Indian National Army joined in this Chalo Delhi ('March on Delhi'). Both Bose and Mutaguchi emphasised the advantages which would be gained by a successful attack into India. Despite the misgivings of several of Mutaguchi’s superiors and subordinates, the 'U' operation was launched.
Stilwell’s forces, which were designated 'X' Force, initially comprised two US-trained and US-equipped Chinese divisions with a Chinese-manned M3 Light Tank battalion and a US long-range penetration brigade known as 'Merrill’s Marauders'.
In 1943 the Thai Phayap Army invasion headed to Xishuangbanna at China, but was driven back by the Chinese nationalist forces.
In October 1943, Major General Sun Li-jen’s Chinese 38th Division began to advance from Ledo in Assam toward Myitkyina and Mogaung while US engineers and Indian labourers extended the Ledo Road behind the division. The 18th Division was repeatedly outflanked by the Marauders and threatened with encirclement.
In 'Thursday', the 'Chindits' were to support Stilwell by interdicting Japanese communications in the region of Indaw. A brigade began marching across the Patkai mountains on 5 February 1944, and at a time early in March three other brigades were flown into landing zones behind Japanese lines by the Royal Air Force and the USAAF, and established defensive strongholds around Indaw.
Meanwhile, the Chinese forces on the Yunnan front ('Y' Force) mounted an attack starting in the second half of April, with nearly 75,000 troops crossing the Salween river on a 185-mile (300-km) front. Soon some 12 Chinese divisions of 175,000 men, under General Wei Li-huang, were attacking Lieutenant General Yuzo Matsuyama’s 56th Division. The Japanese forces in northern Burma were now fighting on two fronts.
On 17 May, control of the 'Chindits' passed from Slim to Stilwell, and the 'Chindits' now moved from the Japanese rear areas to new bases closer to Stilwell’s front. Stilwell now gave the 'Chindits' additional tasks for which they were neither trained not equipped. Nonetheless, they achieved several objectives, but only at the cost of heavy casualties. By the end of June, they had linked with Stilwell’s forces but were exhausted, and were withdrawn to India.
Also on 17 May, a force of two Chinese regiments, Unit Galahad ('Merrill’s Marauders') and Kachin guerrillas captured the airfield at Myitkyina. The Allies did not immediately follow up this success and the Japanese were able to reinforce the town, which fell only after a siege that lasted until 3 August. The capture of Myitkyina airfield nevertheless immediately helped secure the air link from India to Chongqing over 'The Hump'.
By the end of May, the Yunnan offensive, though hampered by the monsoon rains and lack of air support, had succeeded in annihilating the garrison of Tengchong and eventually reached as far as Longling. Strong Japanese reinforcements then counterattacked and halted the Chinese advance.
In Arakan, Christison’s Indian XV Corps renewed the advance on the Mayu peninsula. Ranges of steep hills channelled the advance into three attacks each by one Indian or West African division. Major General H. R. Briggs’s Indian 5th Division captured the small port of Maungdaw on 9 January 1944, and the Indian XV Corps then prepared to capture two railway tunnels linking Maungdaw with the Kalapanzin valley. The Japanese struck first, however, as a strong force from Lieutenant General Tadashi Hanaya’s 55th Division infiltrated the Allied lines to attack Major General F. W. Messervy’s Indian 7th Division from the rear, overrunning the divisional headquarters.
Unlike previous occasions on which this had happened, the Allied forces stood firm against the attack, and supplies were dropped to them by parachute. In the 'Battle of the Admin Box' on 5/23 February, the Japanese concentrated on the Indian XV Corps' administrative area, defended mainly by line of communication troops, but were unable to deal with tanks supporting the defenders, while troops of the Indian 5th Division broke through the Ngakyedauk Pass to relieve the defenders of the box. Although battle casualties were approximately equal, the result was a heavy Japanese defeat. Their infiltration and encirclement tactics had failed to panic Allied troops and as the Japanese were unable to capture enemy supplies, they starved.
Over the next few weeks, the Indian XV Corps' offensive ended as the Allies concentrated on the central front and, after capturing the railway tunnels, the Indian XV Corps halted during the monsoon.
Scoones’s Indian IV Corps had pushed forward two divisions to the Chindwin river, and one division was in reserve at Imphal. There were indications that a major Japanese offensive was building, and Slim and Scoones planned to withdraw and force the Japanese to fight with their logistics stretched beyond the limit. However, they misjudged the date on which the Japanese were to attack, and the strength the Japanese would deploy against some objectives.
Mutaguchi’s 15th Army comprised three infantry divisions and one brigade-sized detachment ('Yamamoto' Force), and initially one regiment of the Indian National Army. Mutaguchi planned to cut off and destroy the forward divisions of the Indian IV Corps before capturing Imphal, while Lieutenant General Kotoku Sato’s 31st Division isolated Imphal by capturing Kohima. Mutaguchi intended to exploit the capture of Imphal by taking the strategic city of Dimapur, in the Brahmaputra river valley as thus would sever the lines of communication to Stilwell’s forces and the air bases used to supply the Chinese over 'The Hump'.
The Japanese crossed the Chindwin river on 8 March. Scoones and Slim were somewhat slow in ordering their forward troops to withdraw, and Major General D. T. Cowan’s Indian 17th Division was cut off at Tiddim. It fought its way back to Imphal with the support of Scoones’s reserve division, supplied by parachute drops. To the north of Imphal, Brigadier M. R. J. Hope-Thompson’s Indian 50th Parachute Brigade was defeated at Sangshak by a regiment of the 31st Division on its way to Kohima. Imphal was thus left vulnerable to an attack by Lieutenant General Masafumi Yamauchi’s 15th Division from the north, but because the Japanese diversionary attack in Arakan had already been defeated, Slim was able to move the Indian 5th Division by air to the central front: two brigades went to Imphal and the third to Dimapur, from where it sent a detachment to Kohima.
By the end of the first week in April, the Indian IV Corps had concentrated on the Imphal plain. The Japanese launched several offensives during the month, but all of these were repulsed. At the start of May, Slim and Scoones began a counter-offensive against the 15th Division to the north of Imphal. Progress was slow, as movement was made difficult by monsoon rains and the Indian IV Corps was short of supplies.
Also at the beginning of April, Sato’s 31st Division reached Kohima. Instead of isolating the small British garrison there and pressing on with his main force to Dimapur, Sato chose to capture the hill station. The siege lasted from 5 to 18 April, when the exhausted defenders were relieved. A new formation headquarters, that of Lieutenant General M. G. N. Stopford’s Indian XXXIII Corps, now assumed control of operations on this front. Major General J. M. L. Grover’s British 2nd Division began a counter-offensive, and by 15 May had prised the Japanese off Kohima Ridge itself. After a pause during which more Allied reinforcements arrived, the Indian XXXIII Corps renewed its offensive.
By now, the Japanese were at the end of their endurance. All their troops, but particularly 15th Division and 31st Division, were starving, and during the monsoon disease spread rapidly through the Japanese ranks. Sato had notified Mutaguchi that his division would withdraw from Kohima at the end of May if it was not supplied and, despite orders to hold, Sato did indeed retreat. The leading troops of the Indian IV Corps and Indian XXXIII Corps met at Milestone 109 on the road linking Dimapur and Imphal road on 22 June, and the siege of Imphal was raised.
Backed by Kawabe, Mutaguchi continued to order renewed attacks. The 33rd Division and 'Yamamoto' Force made repeated efforts, but by the end of June had suffered so many casualties both from battle and disease that they were unable to make any progress. The Japanese finally brought their Imphal operation to an end early in July, and the Japanese retreated painfully to the Chindwin river.
This represented the greatest land defeat to that date in Japanese history. The 15th Army had suffered between 50,000 and 60,000 dead, and 100,000 or more other casualties. Most of these losses were the result of disease, malnutrition and exhaustion. The Allies suffered 12,500 casualties, including 2,269 men killed. Mutaguchi had already relieved all his divisional commanders, and was himself subsequently relieved of command.
During the monsoon from August to November, the 14th Army pursued the Japanese to the Chindwin river. While Major General C. C. Fowkes’s 11th (East Africa) Division advanced down the Kabaw river valley from Tamu, the Indian 5th Division advanced along the mountainous Tiddim road. By the end of November, Kalewa had been recaptured, and several bridgeheads had been seized on the eastern bank of the Chindwin river.
The Allies launched a series of offensive operations into Burma late in 1944 and during the first half of 1945. The command on the front was rearranged in November 1944. The headquarters of General G. J. Giffard’s 11th Army Group was replaced by that of the Allied Land Forces South-East Asia, and the Northern Combat Area Command and the Indian XV Corps were placed directly under this new headquarters. Although the Allies were still attempting to complete the Ledo Road, it was apparent that it would not materially affect the course of the war in China.
The Japanese also made major changes in their command. The most important was the replacement of Kawabe at the head of the Burma Area Army by Lieutenant General Hyotaro Kimura, who then threw Allied planning into confusion by refusing to fight on the Chindwin river. Recognising that most of his formations were weak and short of equipment, he withdrew his forces behind the Irrawaddy river, forcing the Allies to lengthen their lines of communication by a considerable degree.
In Arakan, the Indian XV Corps resumed its advance on Akyab island for the third year in succession. This time the Japanese were far weaker, and retreated before the steady Allied advance. The Japanese evacuated Akyab island on 31 December 1944, and the Indian XV Corps occupied the island without resistance on 3 January 1945 in the amphibious 'Lightning', which was part of the multi-phase 'Talon' operation to take the whole of the Arakan area.
Landing craft had now reached the theatre, and the Indian XV Corps launched amphibious attacks on the Myebon peninsula ('Pungent') on 12 January 1945 and at Kangaw 10 days later during the 'Battle of Hill 170' to cut off the retreating Japanese. There was severe fighting until the end of the month, in which the Japanese suffered heavy casualties.
Important objectives for the Indian XV Corps were the captures of Ramree island and Cheduba island, which would allow the construction of airfields which would support the Allies' operations in central Burma. Most of the Japanese garrison died during the 'Matador' battle for Ramree island and the 'Sankey' assault on Cheduba island. The Indian XV Corps' operations on the mainland were curtailed to release transport aircraft to support the 14th Army.
The Northern Combat Area Command resumed its advance late in 1944, although it was progressively weakened by the aerial extraction of Chinese troops to the main front in China. On 10 December 1944, Major General F. W. Festing’s British 36th Division on the Northern Combat Area Command’s right flank made contact with 14th Army units near Indaw in northern Burma, and five days later Chinese troops on the command’s left flank captured Bhamo. The Northern Combat Area Command made contact with Chiang Kai-shek’s Yunnan armies on 21 January 1945, and the Ledo Road could finally be completed, although by this point in the war its value was uncertain. Chiang ordered the US officer commanding the Northern Combat Area Command, Lieutenant General Daniel I. Sultan, to halt his advance at Lashio, which was captured on 7 March. This was a blow to British plans as it endangered the prospects of reaching Rangoon before the onset of the monsoon, expected at the beginning of May. Winston Churchill, the British prime minister, appealed directly to the US Army chief-of-staff, General George C. Marshall, for the transport aircraft which had been assigned to the North Combat Area Command to remain in Burma. From 1 April, the Northern Combat Area Command’s operations came to an end, and its units returned to China and India. A US-led guerrilla force, OSS Detachment 101, took over the remaining military responsibilities of the Northern Combat Area Command.
The 14th Army, now comprising the Indian IV Corps and Indian XXXIII Corps, made the main offensive effort into Burma. Although the Japanese retreat over the Irrawaddy river forced the Allies into a complete change of their plans, such was the Allies' material superiority that this was done efficiently. The Indian IV Corps was switched in secret from the right to the left flank of the army and aimed to cross the Irrawaddy river near Pakokku and seize the Japanese line-of-communication centre of Meiktila, while the Indian XXXIII Corps continued to advance on Mandalay.
In 'Extended Capital', during January and February 1945, the Indian XXXIII Corps seized crossings over the Irrawaddy river near Mandalay. There was heavy fighting, which attracted Japanese reserves and fixed their attention. Late in February, Major General G. C. Evans’s Indian 7th Division, leading the Indian IV Corps, seized crossings at Nyaungu near Pakokku. The Indian 17th Division and Brigadier C. E. Pert’s Indian 255th Tank Brigade followed the Indian 7th Division across and struck for Meiktila. In the open terrain of central Burma, this force outmanoeuvred the Japanese and fell on Meiktila on 1 March. The town was captured in four days, despite resistance to the last man.
The Japanese tried first to relieve the garrison at Meiktila and then to recapture the town and destroy its defenders, but the attacks were not properly co-ordinated and were repulsed. By the end of March the Japanese had suffered heavy casualties and lost most of their artillery, which was their chief anti-tank weapon, then broke off the attack and retreated to Pyawbwe.
The Indian XXXIII Corps had renewed its attack on Mandalay, which fell to Major General T. W. Rees’s Indian 19th Division on 20 March, though the Japanese held the former citadel, which the British called Fort Dufferin, for another week. Much of the historically and culturally significant portions of Mandalay were burned to the ground.
Although the Allied forces had advanced successfully into central Burma, it was vital to capture the port of Rangoon before the advent of the monsoon to avoid a logistical crisis. In the spring of 1945, the other factor in the race for Rangoon was the years of preparation by the liaison organisation, Force 136, which resulted in a national uprising within Burma and the defection of the entire Burma National Army to the Allied side. In addition to the Allied advance, the Japanese now faced open rebellion behind their lines.
The Indian XXXIII Corps mounted the 14th Army’s secondary drive down the Irrawaddy river valley against stiff resistance by hr 28th Army, while the Indian IV Corps delivered the main attack down the 'Railway Valley', which was also followed by the Sittaung river. The Indian IV Corps began by striking at a Japanese delaying position, held by the remnants of the 33rd Army, at Pyawbwe. The attackers were initially halted by a strong defensive position behind a dry waterway, but a flanking move by tanks and mechanised infantry struck the Japanese from the rear and shattered them.
From this point, the advance down the main road to Rangoon faced little organised opposition. An uprising by Karen guerrillas prevented troops from the reorganised 15th Army from reaching the major road centre of Taungoo before the IV Corps captured it. The leading Allied troops met Japanese rearguards to the north of Bago, some 40 miles (65 km) to the north of Rangoon, on 25 April. Kimura had formed the various service troops, naval personnel and even Japanese civilians in Rangoon into the 105th Independent Mixed Brigade, and this extemporised unit checked the British advance until 30 April and covered the evacuation of the Rangoon area.
The original form of the plan to retake Burma had envisaged the Indian XV Corps making an amphibious assault on Rangoon well before 14th Army reached the capital in order to ease supply problems. This 'Dracula' operation was postponed several times as the necessary landing craft were retained in Europe, and was finally dropped in favour of an attack on Phuket island, off Thailand’s western coast.
Slim feared that the Japanese would defend Rangoon to the last man through the monsoon, which would face the 14th Army with a disastrous supply situation. He therefore asked for 'Dracula' to be remounted at short notice. The naval forces for the attack on Phuket were diverted to 'Dracula', and units of the Indian XV Corps were embarked at Akyab and Ramree islands.
On 1 May, a Gurkha parachute battalion was dropped at Elephant Point, on the Irrawaddy river estuary below Rangoon, and cleared Japanese rearguards from the mouth of the river. The Indian 26th Division landed from the sea on the following day. When these forces arrived they discovered that Kimura had ordered that Rangoon be evacuated, starting on 22 April. After the Japanese withdrawal, Rangoon had experienced an orgy of looting and lawlessness similar to the last days of the British in the city in 1942. On the afternoon of 2 May 1945, the monsoon rains began in full force, and the Allied drive to liberate Rangoon before the rains had thus succeeded with only a few hours to spare.
The leading troops of the Indian 17th and 26th Divisions met at Hlegu, 28 miles (45 km) to the north of Rangoon, on 6 May.
After the Allies had captured Rangoon, a new 12th Army headquarters was created, under the leadership of Stopford, from the headquarters of the Indian XXXIII Corps, to take control of the formations which were to remain in Burma as the 14th Army was withdrawn to prepare for the planned 'Zipper' amphibious invasion of Malaya.
The 28th Army, after withdrawing from Arakan and resisting the Indian XXXIII Corps in the Irrawaddy river valley, retreated into the Pegu Yomas, a range of low jungle-covered hills between the Irrawaddy and Sittang rivers. From these it planned to break out and rejoin the rump of the Burma Area Army. To cover this break-out, Kimura ordered the 33rd Army to mount a diversionary offensive across the Sittang river, despite the fact that the entire army could muster the strength of barely one regiment. On 3 July, the 33rd Army attacked British positions in the 'Sittang Bend', and on 10 July, after a battle for country which was almost entirely flooded, both the Japanese and the Allies withdrew.
The Japanese had attacked too early, for Sakurai’s 28th Army was not ready to start the break out until 17 July, and then it was a disaster. The British had placed ambushes or artillery concentrations on the routes the Japanese were to use. Hundreds of men drowned trying to cross the swollen Sittang river on improvised bamboo floats and rafts. Burmese guerrillas and bandits killed stragglers in the area to the east of the river. The breakout cost the Japanese nearly 10,000 men, half the 28th Army's strength, and the British and Indian casualties were minimal.
The 14th Army, now under the command of Lieutenant General Sir Miles Dempsey, and the Indian XV Corps had returned to India to plan the next stage of the campaign to re-take South-East Asia. A new formation, the Indian XXXIV Corps under the command of Lieutenant General O. L. Roberts, was raised and assigned to the 14th Army for further operations. This was to be the 'Zipper' amphibious assault on the western side of Malaya. The dropping of the atomic bombs on Hiroshima and Nagasaki on 6 and 9 August 1945 ended the war with Japan, however, and thus forestalled this operation, which was undertaken after the war as the quickest way of getting occupation troops into Malaya.
In general, the recovery of Burma is reckoned as a triumph for the British Indian Army and resulted in the greatest defeat the Japanese armies had suffered to that date.
The attempted Japanese invasion of India in 1944 had been launched on the basis of wholly unrealistic premises as, after the Singapore debacle and the loss of Burma in 1942, the British were bound to defend India at all costs. A successful invasion by Japanese forces would have been disastrous. The defence operations at Kohima and Imphal in 1944 have since taken on huge symbolic value as the turning of the tide in British fortunes in the war in the Far East.
After the war had ended, a combination of the pre-war agitation among the Burmese population for independence and the economic ruin of Burma during the four-year campaign made it impossible for the former colonial régime to be resumed on any long-term basis. Within three years, therefore, both Burma and India were independent.
The US objectives in Burma had been to aid the Chinese nationalist régime. Apart from airlift over 'the Hump', these efforts bore no fruit until so near the end of the war that they made little contribution to the defeat of Japan. These efforts have also been criticised as fruitless because of the self-interest and corruption of Chiang Kai-Shek’s régime.