The Gilbert and Marshall Islands campaign were a series of battles fought from August 1942 through February 1944, in the Pacific theatre of World War II between the United States and Japan. They were the first steps of the drive across the Central Pacific by the United States Pacific Fleet and Marine Corps. The purpose was to establish airfields and naval bases that would allow air and naval support for upcoming operations across the Central Pacific. Operation Galvanic and Operation Kourbash were the code names for the Gilberts campaign that included the seizures of Tarawa and Makin, during the Battle of Tarawa on 20–23 November 1943 and the Battle of Makin on 20–24 November 1943. Operation Flintlock and Operation Catchpole were aimed at capturing Japanese bases at Kwajalein, Eniwetok, and Majuro in the Marshall Islands.

The United States Pacific Fleet (USPACFLT) is a theater-level component command of the United States Navy, located in the Pacific Ocean. It provides naval forces to the Indo-Pacific Command. Fleet headquarters is at Joint Base Pearl Harbor–Hickam, Hawaii, with large secondary facilities at Naval Air Station North Island, California.