Located in Southeast Asia, the Indonesia archipelago is the largest island complex in the world, spreading across a chain of thousands of islands between Asia and Australia. The Dutch began to colonize Indonesia in the early 17th century. During World War II Japan occupied the islands from 1942 to 1945, and shortly after Japan's surrender, Indonesia declared its independence. The Dutch were struggling to regain control of Indonesia but were met with strong resistance from the country’s population. In 1949, after four years of war and negotiations, hostilities between the Netherlands and Indonesia ended with the Dutch transferring sovereignty to the Indonesian government. After independence, Indonesia adopted a new constitution providing for a parliamentary system of government. However, the 1945 constitution was revived in 1959 allowing for broad presidential powers. As a result, Indonesia's first free parliamentary election after decades of authoritarian rule took place only in 1999. In recent years, the country has been facing demands for independence in several provinces. The government reached a historic peace agreement with armed separatists in Aceh in 2005, but continues to face a separatist movement in Papua. Indonesia has a well-balanced economy with all major sectors playing an important role. The country has a vast range of mineral resources, and is the only Asian member of the OPEC (Organization of Petroleum Exporting Countries). Supported by appropriate macroeconomic policies, Indonesia continued to make steady economic progress in recent years despite some major natural disasters.