The Dutch East Indies, today Indonesia, was the region of one of the Pacific campaigns during 1942. It was here that the Dutch East India Company held a reasonable source of oil. As Japan's oil supplies were drizzling out, they sent their army to occupied the oil rich regions of the Dutch East Indies.
The Dutch East Indies Campaign began soon after Pearl Harbor. Japanese troops approached Borneo, the largest island in the region, where the Allies had stationed only a few Dutch and British troops. In the month of December, Japanese troops steadily advanced further into Borneo. By the end of January 1942, much of Borneo had fallen including Balikpapan.
The Japanese army was also advancing further elsewhere in the Dutch East Indies. In Celebes and Molocus, they sustained their victories as both fell to the Japanese army in 1942. Japanese troops also landed at Sumatra, where they occupied oil refineries at Palembang as well as key Allied airfields. On the eastern side of Java Japanese paratroopers landed at, and occupied, Timor.
Their troops gradually island hopped their way through the region, and occupied airfields which further expanded Japanese aircraft range. With additional airfields the Japanese air force stepped up their aerial bombardments. Japanese aircraft bombed Allied troop convoys, supply ships and other warships out of the water. In February, hundreds of Japanese planes swarmed across Darwin targeting Allied shipping in port as well as aircraft.
But the Allies still held Java where they had thousands of troops. To occupy Java, Japan sent an invasion fleet which was to transport approximately 35,000 soldiers to Java. Japanese destroyers and cruisers provided naval cover for the transport ships.
On 27 February, an ABDA (American, British, Dutch and Australian) fleet did indeed intercept the Japanese escort fleet at the Java Sea. It was there that Japanese warships wipped out much of the ABDA fleet. The ABDA fleet was initially dispelled, and the Imperial Japanese Navy intercepted those warships that did make an effective withdrawal soon after. The Battle of Java Sea ensured that the Japanese invasion fleet reached its designated target, albeit a little later than planned.
In March, Japanese troops landed at Java. During this period, they landed at three points along Java's coastline; and from there there they advanced further inland. The Japanese had both naval and air superiority for the Battle of Java. Although the Allies had a numerical advantage, without adequate air and naval support they could not hold Java. By the 5 March the Japanese troops occupied the capital Batavia. By the 8th the remaining Allied troops surrendered to the Japanese in Java.
With the fall of Java, the Japanese had effectively won the Dutch East Indies Campaign. The Allies evacuated what troops they could shortly after. The campaign had been a great victory for Japan as they absorbed the Dutch East Indies into their empire. After the fall of Java, the Japanese army headed eastwards toward New Guinea.