After its independence, Indonesia adopted a new constitution providing for a parliamentary system of government. A failure by the constituent assembly to develop a new constitution further weakened the parliamentary system with an already divided parliament among various political parties. As a result, President Sukarno met little opposition in 1959 when he revived the 1945 constitution providing for broad presidential powers.
From 1959 to 1965, Indonesia was under the authoritarian regime of President Sukarno. During this period, Indonesia's relations with the Asian communist countries were close, and domestically, the Indonesian government was close with the Indonesian Communist Party, or PKI. By 1965, many of the mass civic and cultural organizations were controlled by the party. With Sukarno's acquiescence, the PKI began a campaign to establish a "fifth column" by arming its supporters, but it was resisted by army leaders. On Oct. 1, 1965, PKI sympathizers within the military, including elements from Sukarno's palace guard, occupied key locations in Jakarta and kidnapped and murdered six senior generals. Consequently, army troops led by Maj. Gen. Suharto obtained control of the capital.