'Cudgel' was the British second offensive in the Arakan western coastal region of Burma by elements of Lieutenant General W. J. Slim’s 14^th Army, planned for the spring of 1944 originally in concert with 'Bullfrog' and to be followed by 'Bulldozer', but in fact undertaken on its own (December 1943/March 1944).

Between January and May 1942 the Japanese had driven all Allied (British, Indian and Chinese) troops from Burma. During 1943, the Allies had tried a limited offensive into Arakan, the coastal province of Burma. The aim of this 'Cannibal' undertaking had been to secure Akyab island, opposite the end of the Mayu peninsula, as this island possessed a port and an all-weather airfield from which the Imperial Japanese army air force had launched raids on Calcutta and other Indian cities, and which also featured seminally in the Allied plans for the recapture of Burma, and thence Malaya.

'Cannibal' had had failed disastrously: as the British-led Indian army was in the throes of a massive all-volunteer expansion, most of the more numerous Indian units committed to the attack alongside the fewer British units lacked training and experience. During 'Cannibal' exhausted units had been left in the front line and their morale plummeted; Allied tactics and equipment were not suited to operations in the area’s jungle-covered hills; and Japanese units repeatedly achieved surprise by crossing rivers and hills which the Allies had dismissed as impassable. Moreover, the British command structure had proved altogether inefficient, with a single overworked divisional headquarters trying to control a large number of sub-units and also a large line-of-communications area.

In the months after 'Cannibal', the British undertook a major reorganisation of their forces, mandated extensive jungle training, and prepared for a renewed effort in 1944. Under command of Slim’s 14^th Army, the 'Cudgel' offensive was the responsibility of Lieutenant General A. F. P. Christison’s Indian XV Corps.

The upper end of the Mayu peninsula comprises a coastal plain indented by several chaungs (tidal creeks), and is separated from the fertile valley of the Kalapanzin river by the steep and jungle-covered hills of the Mayu range.

Designed to advance as far to the south as the Akyab area to take the airfields that were essential for the support of proposed efforts to retake Rangoon, the preparatory moves for 'Cudgel' were to start in December 1943 from the line between Bawli Bazar in the west and Goppe Bazar in the east. The plan called for Major General H. R. Briggs’s combat-experienced Indian 5^th Division to advance as the corps' right-hand formation along the coastal plain from Bawli Bazar toward Maungdaw, and for Major General F. W. Messervy’s comparatively inexperienced but well trained Indian 7^th Division to push to the south as the corps' left-hand formation from Goppe Bazar toward Buthidaung down the valley of the Kalapanzin river. Farther to the east, Major General G. C. Woolner’s 81^st (West Africa) Division, less one brigade, was to continue its advance down the valley of the Kaladan river but would not become directly embroiled in the battle. Two other divisions, Major General F. W. Festing’s British 36^th Division in Calcutta and Major General C. E. N. Lomax’s Indian 26^th Division at Chittagong, were in reserve.

The provision of air support was entrusted to Air Commodore the Earl of Bandon’s No. 224 Group of the RAF, which was headquartered at Chittagong and possessed some 200 Bristol Beaufighter, Hawker Hurricane, Supermarine Spitfire and Vultee Vengeance warplanes in 14 fighter and fighter-bomber squadrons. The operation could also call on the bombers of Brigadier General H. C. Davidson’s Allied Strategic Air Force as well as the transport aircraft of Brigadier General William D. Old’s Troop Carrier Command which, like the Strategic Air Force, combined British and US units.

Other assets available to the Indian XV Corps at this time were Brigadier W. I. Nonweiler’s British 3^rd Special Service Brigade with two (later four) commandos, and Major General H. L. Davies’s Indian 25^th Division. Also in the area were large numbers of engineer units improving communications and building airfields, and flotillas of small craft operating under the aegis of the Royal Navy.

The advance was initially cautious, but steadily gained momentum. On 9 January 1944, the Indian 5^th Division took the small port of Maungdaw opposite the lower end of the Teknaf peninsula on the western side of the Nef river estuary. While the Indian 5^th Division’s units reduced Japanese positions to the south of Maungdaw, principally the village of Razabil and a hill known from its shape as the Tortoise, the Indian XV Corps prepared to take the next major objective. This was part of the Mayu range where two disused railway tunnels provided part of the west/east route through the hills linking Maungdaw in the west with the towns of Letwedet and Buthidaung in the east within the valley of the Kalapanzin river. To allow men, weapons and equipment to be repositioned for this attack, the Indian 7^th Division’s engineers improved a narrow track, known as the Ngakyedauk Pass, across the hills some 3 miles (4.8 km) to the north, while a large administration area was established at Sinzweya, near the eastern end of the Ngakyedauk Pass.

However, by this time 'Cudgel' was playing into the hands of Lieutenant General Shozo Sakurai, whose 28^th Army was responsible for the defence of Arakan and southern Burma with formations including Lieutenant General Tadashi Hanaya’s 55^th Division in Arakan. Most of the division’s strength (five battalions) was grouped as the 'Sakurai' Column in the Mayu area under the command of Major General Tohutaro Sakurai, the 55^th Division’s infantry group commander. The Japanese were at this time planning their 'U' offensive to take Imphal and Kohima farther to the north, and at Sakurai’s urging Hanaya thus planned a local counterstroke, supported by the 80 aircraft of Lieutenant General Noburo Tazoe’s 5^th Air Division, to pin the British-led forces in Arakan and thus prevent their movement to Imphal.

Lieutenant General Shigesaburo Miyazaki’s 54^th Division was moving to protect the coast in the area to the south of Akyab but took no direct part in the current Arakan operation. Hanaya’s two fragile lines of communication were by track across the Arakan Yomas to Pakokku on the Irrawaddy river and from Prome, again by track, to Taungup and thence by launch to Akyab.

During the months after the end of the 1943 wet monsoon in October, Christison had thus pushed his forces far enough to the south by the middle of January 1944 that he was poised to attack the heavily fortified Japanese line between Maungdaw and Buthidaung. General Sir George Giffard, commanding the Allied 11^th Army Group, had instructed Slim to take this line by mid-January, but the cautious Slim was behind schedule. Meanwhile, the Japanese high command, realising from the exploits of the 'Chindits' in the previous year’s 'Longcloth' operation that neither the jungles nor the hills of Burma were impassable to determined troops, and seeing the British and commonwealth forces in Assam hanging down on a 300-mile (480-km) tail from the main spine on the Brahmaputra river, had decided that the best means for the defence of Burma was attack. The primary Japanese plan for 1944 was the 'U' operation to the west over the Chindwin hills, to cut the lines of communication of Lieutenant General G. A. P. Scoones’s Indian IV Corps at Imphal and destroy the Allied forces in that area.

Sakurai was confident that the 55^th Division could repeat the success of the Japanese forces in the Arakan area during the previous year by delivering a highly effective local counterattack, and perhaps even advance on Chittagong, the port on which the Indian XV Corps relied for its sustenance. Moreover, by launching this 'Ha' (iv) operation during the first week of February, the British would be forced to send reinforcements to Arakan from the central part of the front, so clearing the way for the Japanese 'U' offensive planned to begin in the first week of March as the means of destroying the Indian IV Corps and opening the way to an invasion of eastern India.

So, as a diversion to draw away as many divisions as possible over the other side of the Arakan Yomas, the Japanese would first use penetration tactics to attack and destroy the Allied forces in Arakan. This operation was named 'Ha' (iv), and was planned for implementation on 3 February 1944.

By that date the Indian 5^th Division, supported by tanks, was attacking the Japanese in the 'Tunnels' area (on the road between Maungdaw and Buthidaung) with three brigades 'up', the Indian 7^th Division was attacking Buthidaung in the Mayu valley, and the 81^st (West Africa) Division was far away to the east on the Kaladan river, where its primary effect on the campaign was its drain on Allied air supply resources rather than pressure on the Japanese. Behind these forward divisions were the Indian 26^th and 36^th Divisions.

Hanaya had meanwhile divided his division into four detachments. Two battalions were to hold Akyab, one battalion was to guard the coast of the Mayu peninsula, and two battalions ('Doi' Column) were to hold the redoubts between the Mayu river and the sea, which was being attacked by the six tank-supported brigades of the Indian 5^th and 7^th Divisions. Hanaya entrusted his reconnaissance regiment to check the West Africans in the Kaladan river valley, and this left him with five battalions and an engineer regiment (5,000 men) for offensive operations as Sakurai’s 'Sakurai' Column.

Intended for the penetration role, the 'Sakurai' Column (subdivided into the 'Kubo' Force and 'Tanahashi' Force) was to pass straight through the Indian 7^th Division on the night of 3/4 February, seize Taung Bazar, wheel to the west, cross the Mayu river, and cut the line of communications serving the Indian 5^th and 7^th Divisions. Meanwhile the 'Doi' Column, holding the redoubts, was to attack from the south.

All at first went well for the 'Sakurai' Column, whose units passed through the heart of the Indian 7^th Division in the middle of the night and occupied Taung Bazar 12 miles (19 km) away by the morning. Within an hour one battalion had crossed the Mayu river in captured boats, and by 12.00 on 5 February the whole force was behind the Indian 5^th Division and one detachment had seized Briasco Bridge on the coast road between Wabyin and Bawli Bazar, while the remainder overran the Indian 5^th Division’s headquarters and started attacking the 'Administrative Area' (otherwise the 'Admin Box') at Sinzweya on the lateral road linking Wabyin on the coast and Awlanbyin on the Ngakyedauk Chaung running down into the Kalapanzin river. Here Slim’s new training instructions and orders started to take effect.

The 'Administrative Area', on whose capture the Japanese depended for supplies, closed as a defensive box 1,100 yards (1005 m) square and all of the brigades stood firm. Air supply was made available to the two forward divisions, and this allowed them to continue the fight, improvising where necessary. This was the key to the outcome of the battle, for while the Japanese were fighting a two-dimensional battle on land, the British were able to wage what was in effect a three-dimensional effort by exploiting their superiority in the air.

As a precautionary measure, Gifford ordered the Indian 36^th Division to move to the south from Chittagong.

Hanaya now reinforced his 'Doi' Column and urged it to attack to the north all the harder to come to the aid of the 'Sakurai' Column. The Indian 7^th Division meanwhile cut the 'Sakurai' Column's very thin line of communication running through the area. Sakurai’s code book with wireless frequencies was captured and with it his signals communication list of call signs, with the result that his command and control capabilities started to fail. The 'Admin Box' held out, all ranks and all arms being committed to the defence. Christison at one point wavered, believing his Indian 7^th Division had been overrun, and ordered the Indian 5^th Division to move back across the Mayu range. Slim countermanded this order, however, and urged the Indian 26^th and 36^th Divisions to move forward as swiftly as they could to destroy the Japanese penetration forces. As long as the 'Admin Box' at Sinzweya survived, the Japanese could get no supplies and their offensive was doomed. The box in fact held from 2 to 24 February, when the Ngakyedauk Pass was reopened.

The Japanese put their whole air strength into the battle and flew 350 bomber sorties, but the RAF counterattacked and, although its lost some of its aircraft to Japanese fighters and anti-aircraft fire, the Troop Carrier Command succeeded in delivering 2,710 tons of supplies to the Sinzweya box and the two forward divisions.

On 24 February, with the approval of his army headquarters, Hanaya finally abandoned 'Ha' (iv), and the Japanese extricated themselves without problem. The Indian XV Corps had suffered 3,506 casualties but had managed to hold its ground, thus giving a tremendous fillip to morale throughout the army in India. The Japanese had lost 3,106 dead and 2,229 wounded, as well as 65 fighters to the British loss of three fighters.

But the Japanese in Arakan had nonetheless achieved their object: one Japanese division had thrown two Indian divisions into temporary disarray, and pinned down the equivalent of 6.5 British-led divisions. 'Ha' (iv) had been carried out by about eight battalions totalling not more than 8,000 men, and some 27 Indian, 18 British, seven West African and five Gurkha battalions, with the support of 26 regiments of artillery, had been committed against them. It was no fault of the Japanese soldiers that, as a result of Allied matériel superiority, many of these battalions could be and were switched swiftly by air to the Imphal front to restore the situation there in the early stages of the altogether larger 'U' offensive.

During the 'Ha' (iv) operation, meanwhile, Lieutenant General Shozo Sakurai’s 28^th Army headquarters had relieved Hanaya of responsibility for the Kaladan river front and had on 18 February formed the 'Koba' Force, commanded by Major General Tomotoki Koba and comprising a regimental headquarters, the 55^th Reconnaissance Regiment and the equivalent of three infantry battalions, to face the 81^st (West Africa) Division. Woolner underestimated the Japanese strength and Koba used manoeuvre, ambush and outflanking movement, but never frontal attack, to drive the West Africans 10 miles (16 km) back from Kyauktaw, and then started to press them out of the Kaladan valley.

The attack on Imphal had now started, and Giffard wanted to shift the air transport of the Indian 5^th and 7^th Divisions to that front as soon as possible. He allowed Christison time for the Indian 7^th Division to capture Buthidaung and the Indian 5^th Division to take Razabil before they were relieved by the Indian 26^th and 36^th Divisions on 22 March. The Indian 25^th Division was also moved forward and relieved the Indian 36^th Division, which was to come under the US command of Lieutenant General Joseph W. Stilwell in northern Burma to relieve the 'Chindits'.

Hanaya ordered all his forward units to attack and harass the British forces from all directions and to give an impression of strength during the next four weeks, so as to pin the British and commonwealth forces in the area before he withdrew to monsoon positions. By using false identity badges and other deception methods, he made the 14^th Army’s intelligence apparatus believe that the 54^th Division had moved into the area.

In the Kaladan river valley, Koga followed suit so successfully that the West Africans were expelled completely from the valley and ceased to be a threat to the Japanese flank. Christison’s forces, however, obtained possession of Maungdaw and the much fought over Point 551, which he believed would be a good starting line for the post-monsoon offensive, but Giffard realised that Arakan was a poor area in which to fight the Japanese.

Having inflicted more than 3,500 casualties on the British-led forces in 'Ha' (iv), the Japanese had then caused a further 3,360 casualties in the period before breaking of the monsoon in March ended the campaign, and this excluded casualties from sickness, which were always high.

On 14 July 1944 Giffard recommended that any idea of an offensive in Arakan in the dry season of 1944/45 should be abandoned since at least four or five divisions would appear to be necessary to achieve success.

It is also worth noting that the lightly armed 1/1^st Guerrilla Regiment of the anti-British Indian National Army had been directed to participate in 'Ha' (iv). The battalion left Rangoon early in February, but by the time it reached Akyab early in March 'Ha' (iv) was nearing its end. The battalion subsequently moved up the Kaladan river valley and progressed slowly but successfully against West African units before crossing the Burma/India frontier to occupy Mowdok, near Chittagong.