The 'Battle of Savo Island' is also known as the '1^st Battle of Savo Island' and, to the Japanese, as the '1^st Battle of the Solomon Sea', and was fought between Japanese and predominantly US naval forces within the 'Watchtower' campaign for Guadalcanal island in the Solomon islands group (8/9 August 1942).

The battle also received the nicknamed the 'Battle of the Five Sitting Ducks' by Allied soldiers and sailors, and was the first major naval engagement of the Guadalcanal campaign and also the first of several naval battles in the straits later nicknamed 'Ironbottom Sound' near the island of Guadalcanal.

Responding to the Allied amphibious landings in the south-eastern part of the Solomon islands group, the Imperial Japanese navy created a task force of seven cruisers and one destroyer under the command of Vice Admiral Gunichi Mikawa. This task force sailed from the Japanese base areas in New Britain and New Ireland islands down New Georgia Sound (also known as 'The Slot') to assault the Allied landings by attacking their supporting amphibious forces and their screening forces. The Allied screen consisted of eight cruisers and 15 destroyers under the command of Rear Admiral V. A. C. Crutchley, a British officer seconded to the Royal Australian Navy, but only five cruisers and seven destroyers were involved in the battle. In a night action, Mikawa thoroughly surprised and routed the Allied force, sinking one Australian and three US cruisers, while suffering only light damage in return, in what has been described as the worst defeat in the history of the US Navy or, with the 'Battle of Tassafaronga', as the joint second worst defeat in US naval history exceeded only by the Japanese savaging of the US Pacific Fleet at Pearl Harbor on 7 December 1941.

After the initial engagement, Mikawa feared daylight attacks on his force by Allied carrierborne aircraft and therefore decided to withdraw under cover of night rather than attempt to locate and destroy the Allied invasion transports. The Japanese attacks prompted the remaining Allied warships and the amphibious force to withdraw earlier than planned, and thus before completing the unloading of all the supplies needed by the landed troops, temporarily ceding control of the waters round Guadalcanal to the Japanese. This early withdrawal of the fleet left the Allied ground forces (primarily US Marines) which had landed on Guadalcanal and nearby islands only two days before, in a precarious situation with only very limited supplies, equipment and food with which to hold their beach-heads.

Mikawa’s decision to withdraw rather than attempt to destroy the Allied invasion transports was derived primarily from his concern about possible Allied carrierborne air attacks on his ships in daylight. In reality, the Allied carrier force, similarly fearing Japanese attack, had already withdrawn beyond operational range. This missed opportunity to cripple rather than merely to interrupt the supply of the Allied forces on Guadalcanal contributed to Japan’s failure to recapture the island. At this critical early stage of the campaign, it allowed the Allied forces to entrench and fortify themselves sufficiently to defend the area round Henderson Field until additional Allied reinforcements arrived later in the year.

The 'Battle of Savo Island' was thus the first of five costly, major sea and air/sea engagements fought in support of the ground forces on Guadalcanal itself, as the Japanese sought to counter the US offensive in the Pacific. These sea battles took place after increasing delays by each side to regroup and refit, until 30 November 1942 and the 'Battle of Tassafaronga', after which the Japanese decided to accept heavy losses and now concentrate their own resupply efforts on the use of submarines and barges. The final naval battle, the 'Battle of Rennell Island', took place months later on 29/30 January 1943, by which time the Japanese were preparing to evacuate their remaining land forces and withdraw to reinforced defensive area in the central part of the Solomon islands group.

The 'Watchtower' and 'Ringbolt' landings of 7 August 1942 on Guadalcanal, Tulagi and Florida islands were designed to deny their use to the Japanese as bases, most especially the nearly completed airfield (later named Henderson Field) which the Japanese were constructing on Guadalcanal. If Japanese air and sea forces were allowed to establish forward operating bases in the south-eastern part of the Solomon islands group, they would be in a position to threaten the shipping supply routes between the USA and Australia. The Allies also intended to use the islands as launching points for a campaign to recapture the rest of the Solomon islands group, to isolate or capture the major bases which the Japanese were creating at Rabaul on New Britain island and Kavieng on New Ireland island, and to support the Allied campaign on New Guinea, which was then building strength under the control of General Douglas MacArthur’s South-West Pacific Area. The landings initiated the six-month Guadalcanal campaign.

Overall command of the Allied naval forces in the Guadalcanal and Tulagi operation was vested in Vice Admiral Frank Jack Fletcher, who also commanded the carrier task groups providing air cover, and Rear Admiral Richmond K. Turner commanded the amphibious fleet that delivered the 16,000 Allied troops to Guadalcanal and Tulagi.  Also under Turner’s command was Crutchley’s screening force of eight cruisers, 15 destroyers and five minesweepers. This last force was to protect Turner’s ships and provide gunfire support for the landings. Crutchley commanded his force of primarily US ships from his flagship, the Australian heavy cruiser Australia.

The Allied landings took the Japanese by surprise, and secured Tulagi, the nearby Gavutu and Tanambogo islets, and the airfield under construction on Guadalcanal by the fall of night on 8 August. On 7 and 8 August, Japanese aircraft based at Rabaul attacked the Allied amphibious forces several times, setting on fire the US transport ship George F. Elliott, which later sank, and heavily damaging the destroyer Jarvis. In these air attacks, the Japanese lost 36 aircraft, while the USA lost 19 aircraft, including 14 carrierborne fighters.

Concerned about the losses of his carrierborne fighters, anxious about the threat to his carriers from further Japanese air attacks, and worried about his ships' fuel levels, Fletcher announced that he would withdraw his carrier task forces on the evening of 8 August. Some historians contend that Fletcher’s fuel situation was not at all critical but that Fletcher used it to justify his withdrawal from the battle area, but a biographer of the US admiral has noted that Fletcher concluded that the landing was a success and that no important targets for close air support were at hand. Concerned about the loss of his carrierborne fighter strength, Fletcher assessed that his carriers were threatened by torpedo-bomber attacks and, wanting to refuel before Japanese naval forces arrived, withdrew as he had previously forewarned Turner and Major General Alexander A. Vandegrift, the naval and land force commanders respectively. Turner believed that Fletcher understood that he was to provide air cover until all the transport vessels had been unloaded on 9 August, however. Even though the unloading was going more slowly than planned, Turner decided that without carrierborne air cover he would have to withdraw his ships from Guadalcanal. He planned to unload as much as possible during the night and depart on the following day.

Unprepared for 'Watchtower', the Japanese made an initial response which included air attacks and an attempted reinforcement. Mikawa, commander of the newly created 8^th Fleet headquartered at Rabaul, loaded 519 naval troops on two transports and sent them toward Guadalcanal on 7 August but, after the Japanese had learned that Allied forces at Guadalcanal were stronger than originally reported, the transports were recalled. Mikawa also assembled all the available warships in the area for an attack on the Allied forces at Guadalcanal. At Rabaul were the 'Takao' class heavy cruiser Chokai (Mikawa’s flagship), the light cruisers Tenryu and Yubari of Rear Admiral Mitsuharu Matsuyama’s Cruiser Division 18, and the destroyer Yunagi. On their way from Kavieng were four heavy cruisers of Rear Admiral Aritomo Goto’s Cruiser Division 6: these last were the 'Aoba' class Aoba and Kinugasa and the 'Furutaka' class Furutaka and Kako, giving Mikawa a total of 34 8-in (203-mm) main guns.

The Imperial Japanese navy had trained extensively before the war in night-fighting tactics, a fact of which the Allies were unaware. Mikawa hoped to engage the Allied naval forces off Guadalcanal and Tulagi on the night of 8/9 August, when he could employ his night-battle expertise while avoiding attacks from Allied aircraft, which could not operate effectively at night. Mikawa’s warships rendezvoused at sea near Cape St George, the southernmost point of the island of New Ireland, during the evening of 7 August and then headed east-southeast toward Guadalcanal.

Mikawa opted to take his force to the north of Buka island and then down the eastern coast of Bougainville. The force was to pause to the east of Kieta for six hours on the morning of August 8 and thereby avoid daytime air attacks during their final approach to Guadalcanal. The force would then proceed along the dangerous channel known as 'The Slot', hoping that no Allied aeroplane would see it in the fading light. The Japanese force was in fact sighted in the St George Channel, where their column almost ran into the US submarine S-38, lying in ambush. The submarine was too close to its potential targets to fire torpedoes, but its captain, Lieutenant Commander H. G. Munson, radioed 'Two destroyers and three larger ships of unknown type heading one four zero true at high speed eight miles west of Cape St George'. Once off Bougainville, Mikawa spread his ships over a wide area to mask the composition of his force and launched four reconnaissance floatplanes from his cruisers to scout for Allied ships in the southern part of the Solomon islands group. At 10.20 and 11.10, his ships were spotted by Lockheed Hudson twin-engined reconnaissance aircraft of the Royal Australian Air Force operating from Milne Bay in New Guinea. The first Hudson misidentified the Japanese force as 'three cruisers, three destroyers, and two seaplane tenders'. (Some accounts state that the first Hudson’s crew identified the Japanese ships correctly, but the composition of the Japanese force was changed from the air crew’s report by intelligence officers in Milne Bay.) The Hudson’s crew tried to report the sighting to the Allied radio station at Fall River, New Guinea. Receiving no acknowledgment, it returned to Milne Bay at 12.42 to ensure that the report was received as soon as possible. The second Hudson did not report its sighting by radio, but completed its patrol and landed at Milne Bay at 15.00 to report its sighting of 'two heavy cruisers, two light cruisers, and one unknown type'. For unknown reasons, these reports were not relayed to the Allied fleet off Guadalcanal until 18.45 and 21.30, respectively, on 8 August. The US Navy’s official historian wrote in 1949 that the Hudson’s crew failed to report the sighting until after it had landed and even had tea: the claim made international headlines and was repeated by many subsequent historians, but later research discredited this version of events.

Mikawa’s floatplanes returned at about 12.00 and reported two groups of Allied ships, one off Guadalcanal and the other off Tulagi. By 13.00, Mikawa had reassembled his force and headed south through the Bougainville Strait at a speed of 24 kt. At 13.45, the cruiser force was near the island of Choiseul, to the south-east of Bougainville island. At that time, several surviving Japanese aircraft from the mid-day torpedo raid on the Allied ships off the coast of Guadalcanal flew over the cruisers on their way back to Rabaul and gave them waves of encouragement. Mikawa’s ships had entered the New Georgia Sound (later dubbed 'The Slot') by 16.00 and begun their run toward Guadalcanal. Mikawa communicated his battle plan to his warships: 'On the rush-in we will go from [south] of Savo island and torpedo the enemy main force in front of Guadalcanal anchorage; after which we will turn toward the Tulagi forward area to shell and torpedo the enemy. We will then withdraw north of Savo island.'

Mikawa’s run down 'The Slot' remained undetected by the Allied forces. Turner had requested that Rear Admiral John S. McCain, the US commander of the Allied air forces for the South Pacific Area, conduct extra reconnaissance missions over 'The Slot' during the afternoon of 8 August but, for unexplained reasons, McCain did not order the missions or tell Turner that they were not carried out. Turner thus mistakenly believed that 'The Slot' was under Allied observation throughout the day. However, McCain cannot totally bear the fault, as his patrol craft were few in number, and operated over a vast area at the extreme limit of their endurance. Turner had 15 scout floatplanes of the cruiser force, which were not used during that afternoon and remained on the decks of their cruisers, filled with fuel and constituting as an explosive hazard to the cruisers.

To protect the unloading transports during the night, Crutchley divided the Allied warship forces into three groups. A southern group, comprising the Australian cruisers Australia and Canberra, the US cruiser Chicago and the US destroyers Patterson and Bagley, patrolled between Lunga Point and Savo island to block the entrance between Savo island and Cape Esperance on Guadalcanal island. A northern group, comprising the US cruisers Vincennes, Astoria and Quincy, and the US destroyers Helm and Wilson, conducted a box-shaped patrol between the Tulagi anchorage and Savo island to defend the passage between Savo and Florida islands. An eastern group, comprising the US cruiser San Juan and Australian cruiser Hobart and two US destroyers, guarded the eastern entrances to the sound between Florida and Guadalcanal islands.

Crutchley placed two radar-equipped US destroyers to the west of Savo island to provide early warning of the approach of any Japanese ships. The US destroyer Ralph Talbot patrolled the northern passage and the US destroyer Blue the southern passage, with a gap of 7.5 to 18.5 miles (12 to 30 km) between their unco-ordinated patrol patterns. At this time, the Allies were unaware of all of the limitations of their primitive shipborne radars, such as the fact that the effectiveness of the radar could be greatly degraded by the presence of nearby land masses. Chicago's Captain Howard D. Bode ordered his ship’s radar to be used only intermittently as he was concerned that its use would reveal his position, a decision that conformed with general US Navy radar usage guidelines but which may have been incorrect in this specific circumstance. He allowed a single sweep every 30 minutes with the fire-control radar, but the timing of the last pre-engagement sweep was too early to detect the approaching Japanese cruisers. Wary of the potential threat posed by Japanese submarines to the transport ships, Crutchley placed his remaining seven destroyers as close-in protection around the two transport anchorages.

The crews of the Allied ships were tired after two days of constant alert and action in supporting the landings. Also, the weather was extremely hot and humid, inducing further fatigue. In response, most of Crutchley’s warships went to 'Condition II' during the night of 8 August, which meant that half the crews were on duty while the other half rested, either in their bunks or near their battle stations.

During the evening, Turner called a conference of his command ship off Guadalcanal, together with Crutchley and Vandegrift, to discuss the departure of Fletcher’s carriers and the resulting withdrawal schedule for the transport ships. At 20.55, Crutchley left the southern group in Australia to attend the conference, leaving Bode of Chicago in charge of the southern group. Crutchley did not inform the commanders of the other cruiser groups of his absence, contributing further to the dissipation of command arrangements. Awakened in his cabin, Bode decided not to place his ship in the lead of the southern group’s ships, the customary place for the senior ship, and went back to sleep. At the conference, Turner, Crutchley and Vandegrift discussed the reports of the 'seaplane tender' force reported by the Hudson crew earlier that day, and decided it would not be a threat that night, because seaplane tenders did not normally engage in a surface action. Vandegrift said that he would need to inspect the transport unloading situation at Tulagi before recommending a withdrawal time for the transport ships, and departed at 00.00 to conduct the inspection. Crutchley elected not to return with Australia to the southern force, but instead stationed his ship just outside the Guadalcanal transport anchorage, without informing the other Allied ship commanders of his intentions or location.

As Mikawa’s force neared the area of Guadalcanal, the Japanese ships launched three floatplanes for a final reconnaissance of the Allied ships, and to provide illumination by dropping flares during the forthcoming battle. Although several of the Allied ships heard and/or observed one or more of these floatplanes, starting at 23.45 on 8 August, none of them interpreted the presence of unknown aircraft in the area as an actionable threat, and no one reported the sightings to Crutchley or Turner.

Mikawa’s force approached in a single 1.85-mile (3-km) column led by Chokai, with Aoba, Kako, Kinugasa, Furutaka, Tenryu, Yubari and Yunagi following. At some time between 00.44 and 00.54 on 9 August, look-outs on the Japanese ships spotted Blue about 5.6 miles (9 km) ahead of the Japanese column.

In order to avoid Blue and possible detection, Mikawa changed course to pass to the north of Savo island.  He also ordered his ships to slow to 22 kt to reduce wakes that might make his ships more visible. Four minutes later, Mikawa’s look-outs spied either Ralph Talbot about 10 miles (16 km) distant or a small schooner of unknown nationality. The Japanese ships held their course while training more than 50 guns at Blue, ready to open fire at the first indication that Blue had sighted them. When Blue was less than 1.2 miles (2 km) away from Mikawa’s force, she suddenly reversed course, having reached the end of her patrol track, and steamed away, apparently oblivious to the long column of large Japanese ships steaming by her. Seeing that his ships were still undetected, Mikawa returned to a course to the south of Savo island and increased speed, first to 26 kt and then to 30 kt. At 01.25, Mikawa released his ships to operate independently, and at 01.31 he ordered 'Every ship attack.'

At about this time, Yunagi detached from the Japanese column and reversed direction, perhaps because she had lost sight of the other Japanese ships ahead of her, or perhaps because she had been ordered to provide a rearguard for Mikawa’s force. One minute later, Japanese look-outs sighted a warship to port. This ship was the destroyer Jarvis, which had been heavily damaged on the previous day and was now departing Guadalcanal independently for repairs in Australia. Whether or not Jarvis sighted the Japanese ships is unknown, since her radios had been destroyed. Furutaka launched torpedoes, of which all missed, at Jarvis. The Japanese ships passed as close to Jarvis as 1,205 yards (1100 m), close enough for officers on Tenryu to look down onto the destroyer’s decks without seeing any of her crew moving about. If Jarvis was aware of the Japanese ships passing by, she did not respond in any noticeable way and was torpedoed and sunk on the following day by aircraft from Rabaul. There were no survivors.

Two minutes after sighting Jarvis, the Japanese look-outs sighted the Allied destroyers and cruisers of the southern force at a range of about 13,670 yards (12500 m), silhouetted by the glow from the burning George F. Elliott. Several minutes later, at about 01.38, the Japanese cruisers began launching salvoes of torpedoes at the Allied southern force. At this same time, look-outs on Chokai spotted the ships of the Allied northern force at a range of 17,500 yards (16000 m). Chokai turned to face this new threat, and the rest of the Japanese column followed, while still preparing to engage the Allied southern force ships with their guns.

The crew of Patterson was alert because the destroyer’s captain had taken seriously the earlier daytime sightings of Japanese warships and evening sightings of unknown aircraft, and told his crew to be ready for action. At 01.43, Patterson spotted a ship, probably Kinugasa, 5,470 yards (5000 m) dead ahead and immediately sent a warning by radio and signal lamp: 'Warning! Warning! Strange ships entering the harbor!'. Patterson increased speed to full, and fired star shells toward the Japanese column. Her captain ordered a torpedo attack, but his order was not heard over the noise from the destroyer’s guns.

At about the same moment that Patterson sighted the Japanese ships and went into action, the Japanese floatplanes overhead, on orders from Mikawa, dropped flares directly over Canberra and Chicago. Canberra responded immediately, with Captain Frank Getting ordering an increase in speed, a reversal of an initial turn to port, which kept Canberra between the Japanese warships and the Allied transports, and for her guns to train out and fire at any targets that could be sighted. Less than one minute later, as Canberra's guns took aim at the Japanese, Chokai and Furutaka opened fire on her, scoring numerous hits within a few seconds. Aoba and Kako joined in with gunfire, and within the next three minutes Canberra took up to 24 large-calibre hits. Early hits killed her gunnery officer, mortally wounded Getting, and destroyed both boiler rooms, knocking out power to the entire ship before Canberra could fire any of her guns or communicate a warning to other Allied ships. The cruiser slowed to a halt, on fire, with a 5 to 10° list to starboard, and unable to fight the fires or pump out flooded compartments because of lack of power. Since all of the Japanese ships were on the port side of Canberra, the damage to the Australian cruiser’s starboard side occurred either from shells entering low on the port side and exiting below the waterline on the starboard side, or from one or two torpedo hits on the starboard side. If torpedoes did hit Canberra on the starboard side, then they may have come from a nearby Allied ship, and at this time the US destroyer Bagley was the only ship on that side of the Australian cruiser and had fired torpedoes moments earlier.

Chicago's crew, noting the illumination of their ship by air-dropped flares and the sudden turn by Canberra in front of them, came alert and woke Bode, who ordered his 5-in (127-mm) guns to fire star shells toward the Japanese column, but the shells did not function. At 01.47 a torpedo, probably from Kako, hit Chicago's bow, sending right through the ship a shock wave that damaged the main battery director. A second torpedo hit but failed to detonate, and a shell hit the cruiser’s main mast, killing two men. Chicago steamed to the west for 40 minutes, leaving behind the transports she was assigned to protect. The cruiser fired her secondary batteries at the trailing ships in the Japanese column and may have hit Tenryu, causing slight damage. Bode did not try to assert control over any of the other Allied ships in the southern force, of which he was still technically in command. More significantly, Bode made no attempt to warn any of the other Allied ships or personnel in the Guadalcanal area as his ship headed away from the battle area.

During this time, Patterson engaged in a gun duel with the Japanese column. The US destroyer received a shell hit aft, sustaining moderate damage and and the deaths of 10 men. Patterson continued to pursue and fire at the Japanese ships and may have hit Kinugasa, causing moderate damage, and then lost sight of the Japanese column as it headed to the north-east along the eastern shore of Savo island. Bagley, whose crew sighted the Japanese shortly after Patterson and Canberra, circled completely around to port before firing torpedoes in the general direction of the rapidly disappearing Japanese column: one or two of these torpedoes may have hit Canberra, as noted above. Bagley played no further part in the battle. Yunagi exchanged non-damaging gunfire with Jarvis before exiting the battle area to the west with the intention of rejoining the Japanese column to the north and west of Savo island.

At 01.44, as Mikawa’s ships headed toward the Allied northern force, Tenryu and Yubari separated from the rest of the Japanese column and took a more westward course. Furutaka, either because of a steering problem or to avoid a possible collision with Canberra, followed Yubari and Tenryu. Thus, the Allied northern force was about to be enveloped and attacked from two sides.

When Mikawa’s ships attacked the Allied southern force, the captains of all three US cruisers of the northern force were asleep, with their ships steaming quietly at 10 kt. Although men on all three ships observed flares and/or gunfire from the battle to the south of Savo island or else received Patterson's warning of threatening ships entering the area, it took some time for the crews to go to full alert. At 01.44, the Japanese cruisers began firing torpedoes at the northern force, and at 01.50, directed powerful searchlights at the three northern cruisers and opened fire with their guns.

Astoria's bridge crew called general quarters upon sighting the flares to the south of Savo island at about 01.49. At 01.52, shortly after the Japanese switched on their searchlights and shells began falling around the ship, Astoria's main gun director crews spotted the Japanese cruisers and opened fire. Waking to find his ship already in action, Astoria's captain rushed to the bridge and ordered the guns to cease fire as he was concerned that his ship might be firing on friendly forces. As shells continued to plummet round his ship, the captain ordered fire to be resumed less than a minute later. Chokai had found the range, and Astoria was quickly hit by numerous shells and set on fire. Between 02.00 and 02.15, Aoba, Kinugasa and Kako joined Chokai in pounding Astoria, destroying the cruiser’s engine room and bringing the flaming ship to a halt. At 02.16, one of Astoria's remaining operational main gun turrets fired at Kinugasa's searchlight, but missed and hit one of Chokai's forward turrets, putting it out of action and causing moderate damage to the ship. Astoria sank at 12.16 after all attempts to save her had failed.

Quincy had also seen the aircraft flares over the southern group’s ships, received Patterson's warning and had just sounded general quarters and was coming alert when the Japanese searchlights were activated. Quincy's captain gave the order to open fire, but the gun crews were not ready. Within a few minutes, Quincy had been caught in a crossfire between Aoba, Furutaka and Tenryu, and was hit heavily and set on fire. Quincy's captain ordered his cruiser to charge toward the Japanese eastern column, but as she turned to do so Quincy was hit by two torpedoes from Tenryu, sustaining severe damage. Quincy managed to fire a few main-gun salvoes, one of which hit Chokai's chart room 20 ft (6 km) from Mikawa, and killed or wounded 36 men, although Mikawa was not injured. At 02.10, the detonation of Japanese shells killed or wounded almost all of Quincy's bridge crew, including the captain. At 02.16, the cruiser was hit by a torpedo from Aoba, and the ship’s remaining guns were silenced. Quincy sank, bow first, at 02.38.

Like Quincy and Astoria, Vincennes sighted the aerial flares to the south and, moreover, actually sighted gunfire from the southern engagement. At 01.50, when the US cruisers were illuminated by the Japanese searchlights, Vincennes hesitated to open fire, believing that the searchlight’s source might be those of friendly ships. Shortly after tis, Kako opened fire on Vincennes, which responded with her own gunfire at 01.53. As Vincennes began to receive damaging shell hits, her commander, Captain Frederick L. Riefkohl, ordered an increase of speed to 25 kt, but soon after this, at 01.55, two torpedoes from Chokai hit, causing heavy damage. Kinugasa now joined Kako in the pummelling of Vincennes, which scored one hit on Kinugasa that caused moderate damage to her steering engines. The rest of the Japanese ships also fired on and hit Vincennes as many as 74 times, and, at 02.03, another torpedo, this time from Yubari, hit the US cruiser. With all boiler rooms destroyed, Vincennes slowed to a halt, burning everywhere and listing to port. At 02.16, Riefkohl ordered the crew to abandon ship, and Vincennes sank at 02.50.

During the engagement, the US destroyers Helm and Wilson found it hard to see the Japanese ships. Both destroyers briefly fired at Mikawa’s cruisers but neither inflicted nor received damage.

At 02.16, the Japanese columns ceased fire on the northern Allied force as they moved out of range round the northern side of Savo island. Ralph Talbot encountered Furutaka, Tenryu and Yubari as they cleared Savo island. The Japanese ships fixed the US destroyer with searchlights and hit her several times with gunfire, causing severe damage, but Ralph Talbot escaped into a nearby rain squall, and the Japanese ships left her behind.

At 02.16 Mikawa spoke with his staff about whether or not they should turn to continue the battle with the surviving Allied warships and try to sink the Allied transports in the two anchorages. Several factors influenced Mikawa’s resulting decision: the Japanese ships were scattered and would take some time to regroup; the ships needed to reload their torpedo tubes, a labour-intensive task which would take some time; Mikawa also did not know the number and locations of any remaining Allied warships and his ships had expended much of their ammunition; and most importantly, Mikawa had no air cover and believed that US aircraft carriers were in the area.

Mikawa must also have been aware that the Imperial Japanese navy had no more heavy cruisers in production, and thus would be unable to replace any that might be lost to air attack on the following day if he remained near Guadalcanal. He was unaware that the US carriers had withdrawn from the battle area and would not be a threat the next day. Although several of Mikawa’s staff urged an attack on the Allied transports, the consensus was to withdraw from the battle area, and at 02.20 Mikawa therefore ordered his ships to retire.

At 04.00 on 9 August, Patterson came alongside Canberra to assist the cruiser in fighting her fires, and by 05.00 it appeared that the fires were almost under control. But Turner, who at this time intended to withdraw all Allied ships by 06.30, ordered the ship to be scuttled if she was unable to accompany the fleet. After the survivors had been removed, therefore, the US destroyers Selfridge and Ellet sank Canberra, a task which took some 300 shells and five torpedoes.

Later in the morning of 9 August, Vandegrift advised Turner that he needed more supplies unloaded from the transports before they withdrew. Turner therefore postponed the ships' withdrawal until the middle of the afternoon. In the meantime, Astoria's crew tried to save their ship from sinking, but the cruiser’s fires eventually grew completely out of control, however, and the ship sank at 12.15.

On the morning of 9 August, an Australian coastwatcher on Bougainville island radioed a warning of a Japanese air attack on the way from Rabaul. The Allied transport crews ceased unloading for a time, but were puzzled when the air attack did not materialise. Allied forces did not discover until after the war’s end that this Japanese attack was in fact concentrated on Jarvis in the area to the south of Guadalcanal, sinking her with all hands.

The Allied transports and warships had all departed the Guadalcanal area by the fall of night on 8 August. During the 'Battle of Savo Island', three US heavy cruisers (Astoria, Quincy and Vincennes) and one Australian heavy cruiser (Canberra) had sunk or been scuttled. Chicago spent the next six months in dry dock, returned to Guadalcanal late in January 1943 and was promptly sunk in the campaign’s last naval engagement, the 'Battle of Rennell Island'.

Late in the evening of August 9, Mikawa in Chokai released the four cruisers of Cruiser Division 6 to return to their home base at Kavieng. At 08.10 on 10 August, Kako was torpedoed and sunk by the US submarine S-44 some 68 miles (110 km) from her destination. The other three cruisers picked recovered all but 71 of her crew and went on to Kavieng.

Admiral Isoroku Yamamoto, the commander of the Combined Fleet, signaled a congratulatory note to Mikawa on his victory. At a later date, however, when it became clear that he had missed an opportunity to destroy the Allied transports, he was intensely criticised by his comrades.

From the battle to a time some months later, almost all Allied supplies and reinforcements sent to Guadalcanal came in small convoys of transport ships, primarily during daylight hours while Allied aircraft from the New Hebrides islands group and Henderson Field, as well as any available aircraft carriers, flew cover. During this time, Allied forces on Guadalcanal received barely enough ammunition and provisions to withstand the several Japanese offensives to retake the island.

Despite their defeat in this battle, the Allies eventually won the Guadalcanal campaign, an important step in the eventual defeat of Japan. In hindsight, one can see that had Mikawa elected to risk his ships in attacking the Allied transports on the morning of 9 August, he could have improved the chances of Japanese victory in the Guadalcanal campaign at its inception, and the course of the war in the South Pacific Area could have taken a different course. Although the Allied warships at Guadalcanal on the night of 8/9 August were comprehensively out-thought and out-fought, the transports were unaffected. Many of these same transports were later used on numerous other occasions to bring crucial supplies and reinforcements to Allied forces on Guadalcanal over the succeeding months. Mikawa’s decision not to destroy the Allied transport ships when he had the opportunity would prove to be a crucial strategic mistake for the Japanese.

A formal US Navy board of inquiry, the Hepburn Investigation, prepared a report on the battle after interviewing most of the major Allied officers involved over a period of several months starting in December. The report recommended official censure for only one officer, Bode, for failing to broadcast a warning of approaching Japanese ships. The report stopped short of recommending formal action against other Allied officers, including Fletcher, Turner, McCain, Crutchley and Riefkohl. The careers of Turner, Crutchley, and McCain seem not to have been adversely affected by the defeat or the mistakes they made in contributing to it. Riefkohl never again commanded a ship. On learning that the report was going to be especially critical of his actions, Bose shot himself in his quarters at Balboa, Panama Canal Zone, on 19 April 1943, and died on the following day.

Turner assessed why his forces were so soundly defeated in the battle: 'The Navy was still obsessed with a strong feeling of technical and mental superiority over the enemy. In spite of ample evidence as to enemy capabilities, most of our officers and men despised the enemy and felt themselves sure victors in all encounters under any circumstances. The net result of all this was a fatal lethargy of mind which induced a confidence without readiness, and a routine acceptance of outworn peacetime standards of conduct. I believe that this psychological factor, as a cause of our defeat, was even more important than the element of surprise.'

The report of the inquiry led the US Navy to make many operational and structural changes. The latter included the installation on all the older US cruisers of emergency Diesel-electric generators, and the ships' fire mains were changed to a vertical loop design that could be broken many times yet still function. During the 'Battle of Savo Island', many ship fires were attributed to aviation facilities filled with fuel, oil and aircraft. Motor boats were also filled with petrol and also caught fire. In some cases, these facilities were dead amidships, presenting a perfect target for Japanese ships at night. Lockers containing fused ready-use ammunition added to the destruction, and it was noted that the lockers were never close to being depleted, and thus that they contained much more ammunition than they needed. A focus was put on removing or minimising the quantities of flammable materials in midship locations.

The Chief of Naval Operations, Admiral Ernest J. King, ordered these and other sweeping changes be made before ships entered surface combat in the future.