The Dutch arrived in Indonesia in the early 1600's and formed the Dutch East India Company, the VOC. They facilitated trade between the Dutch and Indonesians, and had the support of their government.
Dutch and Portuguese Fight for Indonesia;
The VOC had a monopoly on the spice trade, and became very wealthy and powerful. They slowly and forcibly took over docks and land all across Indonesia to better control trade and gain more influence. The Dutch government continued to support the VOC, which had its own private army.
Japanese Occupation of Indonesia
After colonizing Indonesia, the Dutch started to exploit the abundance of spices in Indonesia. Spices were a delicacy, and were very expensive in Europe. There was few spices that could be made in Europe, so the Dutch had to take spices from Indonesia.
The Portuguese arrived in Indonesia in the 1600's to steal valuable nutmeg, cloves, and cubeb pepper. The VOC was formed in 1602 to control trade in the region, because of its important location in trading goods. The VOC was backed by the Dutch government, who wrestled for control of Indonesia. The Dutch managed to bring Indonesia under its control by 1610.
In World War II, Imperialist Japan took over control of Indonesia. The Japanese did not really exploit Indonesia, because they had other things to do. After Japan was defeated by the allies, the Dutch tried to reclaim Indonesia.
In Indonesia, there was growing nationalism, and many did not want Dutch rule. The Dutch gave high taxes, exploited resources, and did not invest very much into the country, All this caused strong nationalism, and Indonesia finally gained independence.