The Indonesian legal system is based on Roman-Dutch law, modified by custom and Islamic law. Sources of law are Islamic law, statutory legislation, presidential instructions, and official compilations of Islamic law.

European explorers arrived in the region in the 16th century, and the Dutch East India Company was founded in 1602. The Dutch established a trading post on the north coast of Java, later named Jakarta. The Dutch gradually asserted political and military control beyond Java from the 18th century until most of archipelago was under Dutch rule by the start of the 20th century.

Under Dutch rule, the Netherlands Indies population was divided into Europeans, Natives, and Foreign Orientals. The Dutch established separate tribunals for Europeans and Natives. Indonesians were subject to adat law (custom law), with the Netherlands East Indies divided into several jurisdictions based on cultural and linguistic criteria. Dutch scholars identified and classified 19 different systems of customary law in the region. In areas under direct rule, there were European courts, native courts, and general courts for all of the population. In areas under indirect rule, there were native courts applying adat with very limited criminal jurisdiction and no jurisdiction over Europeans or foreigners.

The basic principle was dominance of the received civil law system, and application of adat for natives as far as it was not replaced by statute. The first legislation relating to the application of Islamic law was an 1882 Royal Decree establishing a Priest Court for Java and Madura, although the Decree acknowledged that most Indonesians were also subject to adat law administered by native courts. The Priest Court had jurisdiction over Muslim family and inheritance law where all parties were Muslim and awqaf, and had concurrent jurisdiction with the native courts of Java and Madura. The Priest Court was composed of a President selected from the native courts officers and three to eight qadis, all appointed by the Governor-General.

Subsequent legislation by Dutch authorities was also of a largely of regulatory and administrative nature. Independence was declared two days after Japanese occupying forces withdrew in 1945. Calls for the reform of marriage laws led to various proposals from members of government, womens groups and the National Institute for Law Reform from 1945 to 1973, but conflicting interests prevented any consensus being reached. The only statutory reform of Muslim personal status in that period was the enactment of the Muslim Marriage and Divorce Registration Law 1946 requiring registration.