Battle of The Java Sea - Background

Background

The Japanese invasion of the Dutch East Indies progressed at a rapid pace as they advanced from their Palau Islands colony and captured bases in Sarawak and the southern Philippines. They seized bases in eastern Borneo and in northern Celebes while troop convoys, screened by destroyers and cruisers with air support provided by swarms of fighters operating from captured bases, steamed southward through the Makassar Strait and into the Molucca Sea. To oppose these invading forces was a small force, consisting of Dutch, American, British & Australian warships—many of them of World War I vintage—initially under the command of Admiral Thomas C. Hart.

On 23 January 1942, a force of four American destroyers attacked a Japanese invasion convoy in Makassar Strait as it approached Balikpapan in Borneo. On 13 February, the Allies fought unsuccessfully—in the Battle of Palembang—to prevent the Japanese from capturing the major oil port in eastern Sumatra. On the night of 19/20 February, an Allied force attacked the Eastern Invasion Force off Bali in the Battle of Badung Strait. Also on the 19th, the Japanese made two air raids on Darwin, one from carrier based planes and the other by land based planes. They attacked and wrecked the port at Darwin in northern Australia which rendered it useless as a supply and naval base to support operations in the East Indies.

Shortly before the battle commenced, the odds were not good for the Allied forces. They were disunited (ships came from four separate navies) and demoralized by constant air attacks, and a general sentiment that the Japanese were unbeatable. In addition, the coordination between Allied navies and air forces was poor.