September 30th Movement Launches Coup Attempt in Indonesia

Context

By the mid-1960s President Sukarno sought to balance the Indonesian Army against the rapidly expanding Communist Party of Indonesia (PKI). The PKI had gained influence through land-reform campaigns and close ties to Sukarno’s anti-imperialist foreign policy, which drew support from China and the Soviet Union. Army leaders, many of whom received training and equipment from the United States, viewed the PKI’s proposal to create an armed “fifth force” of workers and peasants as a direct threat to their institutional power.

What Happened

Late on 30 September 1965 a group of officers led by Lieutenant Colonel Untung Syamsuri assembled troops at Halim Perdanakusuma Air Force Base south of Jakarta. In the early hours of 1 October, seven detachments moved through the capital to seize seven senior generals. Three generals were killed at their homes; three others were captured alive. General Abdul Haris Nasution escaped by jumping over a wall into the Iraqi embassy compound, though his aide Lieutenant Pierre Tendean and his young daughter Ade Irma Suryani were killed. The victims’ bodies were later dumped in an abandoned well at Lubang Buaya near the airbase.

Aftermath

The conspirators occupied the national radio station and broadcast that they had acted to forestall a supposed “Council of Generals” coup. They claimed President Sukarno was under their protection. Sukarno, who had gone to Halim that morning, refused to endorse the group. From his nearby Kostrad headquarters, Major General Suharto quickly rallied loyal units, retook the radio station, and isolated the Halim base. By nightfall on 1 October the movement had collapsed in Jakarta. PKI chairman D. N. Aidit fled the capital the next day.

Legacy

Suharto and army leaders placed responsibility for the killings on the PKI, unleashing a nationwide purge that killed hundreds of thousands of suspected communists and their sympathizers. Sukarno was gradually stripped of authority and Suharto assumed emergency powers, establishing the New Order dictatorship that governed Indonesia until 1998. The events remain contested; official narratives long emphasized PKI orchestration while independent accounts highlight the limited and improvised nature of the original plot.