De facto Republic Indonesia was a short-lived unrecognized state between 1946-1949

De facto Republic Indonesia was a short-lived unrecognized state between 1946-1949 on parts of Java and Sumatra in todays Indonesia. It merged with The United States of Indonesia (Dutch: Verenigde Staten van Indonesië', Indonesian: Republik Indonesia Serikat, abbreviated as RIS) in 1949.

The Dutch recognised de facto republican control over Sumatra, Java and Madura, and the Republic of Indonesia agreed to the principle of a federal Indonesia in which it would be one state following the Linggadjati Agreement.

The agreement comprised an introduction, 17 articles and a final clause. According to the terms, the Netherlands agreed to recognize the Republic as exercising de facto authority over Java, Sumatra and Madura (Article 1). The Republic would become one of three constituent states of the federal United States of Indonesia, along with the State of Borneo and the Great Eastern State, comprising the region of the Eastern Dutch East Indies known as the Great East. Any region that did not want to join the USI could determine its relationship with the USI and the Netherlands through a democratic process. (Articles 2, 3 & 4). The constitution of the USI would be drawn up by an elected Constituent Assembly. The Netherlands Indies, together with the Netherlands, Suriname, and the Netherlands Antilles, would form a Netherlands-Indonesian Union with the Dutch monarch as official head of this Union (Articles 5, 7 & 8 ). Both the United States of Indonesia and the Union which would be established by 1 January 1949 at the latest (Article 12). Once the agreement was signed, both parties would reduce their armed forces (Article 16). Any disputes regarding the agreement would be resolved by arbitration in the event that joint consultation failed. The last resort was to be a ruling by the president of the International Court of Justice.

Both sides made concessions. The republicans committed to the establishment of a federal Indonesian state, while the Dutch conceded the inclusion of Sumatra in the Republic of Indonesia as well as Java. The two sides reached a compromise on the form of the relationship between the USI and the Netherlands. The Dutch had wanted a political union (Dutch: staatsverband), while the republicans had wanted merely an alliance (Dutch: bondgenootschap). The final agreement was for the USI to be a "sovereign and equal partner in a union", although the Dutch succeeded in persuading the republicans to agree to the Dutch monarch being the head of this union.