War in the Pacific: The First Year
A Guide to
the War in
the Pacific
History of Outbreak

Pre-War Guam: 1941

The Insular Force Guard

Japan's Pacific Gamble

The Chamorro

Sailors and Ships


War in the Pacific: Outbreak of the War

History of the Outbreak of the War in the Pacific

The underlying causes of the outbreak of the war in the Pacific relate to Japan's desire to effectively compete with the industrialized nations of western Europe and the United States. As an island nation, Japan had very few natural resources of her own and, therefore, looked elsewhere for raw materials to supply her growing industrial base. Japan felt that Asia and the western Pacific islands were inside her spheres of influence, and resented the presence of other colonial powers such as Britain, France, Holland, and the United States. Following the invasion of China, and subsequent occupation of French Indo-China, the Japanese felt increasing pressure from the United States, including economic embargoes, and concluded that war was the only solution. Japan's need for resources found expression in a determination to achieve dominance in the Pacific by forceful means. The opening attacks caught the Allies by surprise and unprepared for war; the initial Japanese victories were stunning. Japan controlled a huge area in the Pacific, and her impressive victories continued.

Once the decision for war had been reached, the Japanese strategists decided a surprise raid on Pearl Harbor was the best chance of gaining the necessary objectives in Asia and the Pacific. The attack on Pearl Harbor corresponded with attacks on other Allied possessions in the region, such as the Philippines, Guam, Wake Island, the Dutch East Indies, Malaya, and Hong Kong. Although Wake Island and Guam were not rich in natural resources, the Japanese wanted these islands to consolidate their holdings throughout the western Pacific and strengthen their defensive perimeter.

Map of the South Pacific. (click on image for an enlargement in a new window)