World War II-era air navigation chart of the Pacific, prepared for the War and Navy Department Agencies.
Many radio stations have their call letters provided in Morse Code. A navigational sunline and ship DR (dead reckoning) positions are plotted with times (in UTC) in pencil.
By 1944, the Pacific Theatre had shifted west, as American troops moved toward Japan's inner line of defense. In the Japanese Mandate of the Marshall Islands, Kwajalein was the site of major bombardment during the Battle of Kwajalein (31 January - 3 February 1944). During this battle, the lightly defended Majuro Atoll was also captured by American troops who built a naval base there. Another major base was Naval Advance Base Espiritu Santo, the island under the administration of the Anglo-French Condominium of the New Hebrides, which became the second-largest base in the Pacific after Pearl Harbor.