Westerling's operation, which started in December 1946 and ended in February 1947, succeeded in eliminating the insurgency and undermining local support for the Republicans by instituting summary executions of suspected enemy fighters.
On 15 November 1946 the Linggadjati Agreement (Linggajati in modern Indonesian spelling) was concluded by the Dutch administration and the unilaterally declared Republic of Indonesia in the village of Linggajati, Kuningan Regency, near Cirebon in which the Dutch recognised the republic as exercising de facto authority in Java, Madura and Sumatra.
[9] In violation of the Linggadjati Agreement hundreds of freedom fighters from Java made the crossing to assist 'their brothers on Celebes', carrying enormous amounts of smuggled weapons.
What made things even more confusing was the fact that the resistance of the Indonesians became fragmented into all kinds of - competing - parties, which in turn sometimes entered into alliances with criminal gangs (Rampokkers).
The method of killing by these Indonesian 'nationalistic' groups was to lay (or hold) the victim on the ground and cut his neck with a badik (dagger knife).
[10] [11] [12] Despite the Malino Conference in July 1946 which established local federal states in Dutch-controlled parts of Indonesia, the Sulawesi government's effectiveness was weakened by the poor economic situation, agricultural famines and a non-existent civil administration.
[13] The Indonesian Republic in Java provided training for Sulawesi guerrillas and even dispatched Javanese forces, using the ports of Polongbangkeng and Barru for landing troops and supplies.
[14] The failure of conventional tactics prompted the Netherlands East Indies government to dispatch the maverick counter-insurgency expert Raymond Westerling who initiated a three-month pacification campaign from December 1946 to February 1947.
[16] According to Westerling, pacifying Sulawesi, without losing thousands of innocent lives could only be accomplished by instituting summary justice on the spot of suspected enemy fighters, who were generally executed.
[17] Based on their information and that of the Dutch military intelligence service, the DST surrounded one of more suspected villages during night, after which they drove the population to a central location.
However, the Netherlands East Indies government and the Dutch army command soon realised that Westerling's notoriety led to growing public criticism.
Mohammed Natzir of the Indonesian Historical Commission of the Armed Forces also calls the figure of 40,000 deaths fiction and a propaganda measure of the Republican government against the Dutch occupation of that time.
"They painted me as a bloodthirsty monster, who attacked the people of Celebes by fire and sword and exposed all those, who in the interest of Indonesia's national independence resisted Dutch rule, to a merciless campaign of repression".
Westerling stated he had based his tactics on the premise that he performed the role of policeman, combating terror: "I arrested terrorists, not because they acted as instigators of the Republican government... but because they made themselves guilty of open and unmistaken crimes...I never had them [his troops] bombard a village, nor did I take the hut of innocent under fire.
[23] In 1949, the Dutch–Indonesian agreement on transfer of power stipulated neither country would call the other on its wartime offences, thus ruling out any attempt by Indonesia to press for Westerling's extradition.
[25] In March 2020, Hague District Court ordered the Dutch government to pay damage compensation ranging from €123 to €10,000 to relatives of 11 men executed in South Sulawesi campaign.