On 7 August 1942, Allied forces (primarily U.S.) landed on Japanese-occupied Guadalcanal, Tulagi, and Florida Islands in the Solomon Islands. The landings on the islands were meant to deny their use by the Japanese as bases for threatening the supply routes between the U.S. and Australia, and to secure the islands as starting points for a campaign with the eventual goal of neutralizing the major Japanese base at Rabaul while also supporting the Allied New Guinea campaign. The landings initiated the six-month-long Guadalcanal campaign.
After the Battle of the Eastern Solomons on 24–25 August, in which the aircraft carrier USS Enterprise was heavily damaged and forced to travel to Pearl Harbor, Hawaii, for a month of major repairs, three U.S. carrier task forces remained in the South Pacific area. The task forces included the carriers USS Wasp, Saratoga, and Hornet plus their respective air groups and supporting surface warships, including battleships, cruisers, and destroyers, and were primarily stationed between the Solomons and New Hebrides (Vanuatu) islands. At this location, the carriers were charged with guarding the line of communication between the major Allied bases at New Caledonia and Espiritu Santo, supporting the Allied ground forces at Guadalcanal and Tulagi against any Japanese counteroffensives, covering the movement of supply ships to Guadalcanal, and engaging and destroying any Japanese warships, especially carriers, that came within range.
burns after being torpedoed on 14 September
The area of ocean in which the U.S. carrier task forces operated was known as "Torpedo Junction" by U.S. forces because of the high concentration of Japanese submarines in the area.
On 31 August, USS Saratoga was torpedoed by Japanese submarine I-26 and was out of action for three months for repairs.
On 14 September, USS Wasp was hit by three torpedoes fired by Japanese submarine I-19 while supporting a major reinforcement and resupply convoy to Guadalcanal and almost engaging two Japanese carriers Shōkaku and Zuikaku (which withdrew just before the two adversaries came into range of each other's aircraft). With power knocked out from torpedo damage, Wasp's damage-control teams were unable to contain the ensuing large fires, and she was abandoned and scuttled.
Although the U.S. now had only one operational carrier (Hornet) in the South Pacific, the Allies still maintained air superiority over the southern Solomon Islands because of their aircraft based at Henderson Field on Guadalcanal. However, at night, when aircraft were not able to operate effectively, the Japanese were able to operate their ships around Guadalcanal almost at will. Thus, a stalemate in the battle for Guadalcanal developed — Allies delivering supplies and reinforcements to Guadalcanal during the day, and the Japanese doing the same by warship (called the "Tokyo Express" by the Allies) at night — with neither side able to deliver enough troops to the island to secure a decisive advantage. By mid-October, both sides had roughly an equal number of troops on the island. The stalemate was briefly interrupted by two large-ship naval actions. On the night of 11–12 October, a U.S. naval force intercepted and defeated a Japanese naval force en route to bombard Henderson Field in the Battle of Cape Esperance. But just two nights later, a Japanese force that included the battleships Haruna and Kongō successfully bombarded Henderson Field, destroying most of the U.S. aircraft and inflicting severe damage on the field's facilities. Although still marginally operational, it took several weeks for the airfield to recover from the damage and replace the destroyed aircraft.
Grumman F4F Wildcat
as she conducts air operations in the South Pacific on 24 October 1942.
The U.S. made two moves to try to break the stalemate in the battle for Guadalcanal. First, repairs to Enterprise were expedited so that she could return to the South Pacific as soon as possible. On 10 October, Enterprise received her new air group (Air Group 10) and on 16 October, she left Pearl Harbor; and on 23 October, she arrived back in the South Pacific and rendezvoused with Hornet and the rest of the Allied South Pacific naval forces on 24 October, 273 nmi (506 km; 314 mi) northeast of Espiritu Santo.
Second, on 18 October, Admiral Chester Nimitz, Allied Commander-in-Chief of Pacific Forces, replaced Vice Admiral Robert L. Ghormley with Vice Admiral William Halsey, Jr. as Commander, South Pacific Area: this position commanded Allied forces involved in the Solomon Islands campaign. Nimitz felt that Ghormley had become too myopic and pessimistic to lead Allied forces effectively in the struggle for Guadalcanal. Halsey was reportedly respected throughout the U.S. naval fleet as a "fighter". Upon assuming command, Halsey immediately began making plans to draw the Japanese naval forces into a battle, writing to Nimitz, "I had to begin throwing punches almost immediately."
The Japanese Combined Fleet was also seeking to draw Allied naval forces into what was hoped to be a decisive battle. Two fleet carriers—Hiyō and Jun'yō—and one light carrier—Zuihō—arrived at the main Japanese naval base at Truk Atoll from Japan in early October and joined Shōkaku and Zuikaku. With five carriers fully equipped with air groups, plus their numerous battleships, cruisers, and destroyers, the Japanese Combined Fleet, directed by Admiral Isoroku Yamamoto, was confident that it could make up for the defeat at the Battle of Midway. Apart from a couple of air raids on Henderson Field in October, the Japanese carriers and their supporting warships stayed in the northwestern area of the Solomon Islands, out of the battle for Guadalcanal and waiting for a chance to approach and engage the U.S. carriers. With the Japanese Army's next planned major ground attack on Allied forces on Guadalcanal set for 20 October, Yamamoto's warships began to move towards the southern Solomons to support the offensive and to be ready to engage any Allied (primarily U.S.) ships, especially carriers, that approached to support the Allied defenses on Guadalcanal.