Indonesian Army Day Date in the current year: December 15, 2024

The Indonesian Army (Tentara Nasional Indonesia Angkatan Darat) is one of the three branches of the Indonesian National Armed Forces, along with the Indonesian Navy and the Indonesian Air Force. Its estimated strength is 300,000 active personnel. The structure of the Indonesian Army includes the headquarters, 15 military region commands, the Army Strategic Reserves Command (Kostrad), the Special Forces Command (Kopassus), and various adjunct units.

Indonesia’s need for its own national army arose when Sukarno proclaimed the independence of Indonesia in August 1945, following the end of Japanese occupation. However, the Dutch government was determined to make Indonesia a Dutch colony again and secured British support, forcing Indonesians to protect the sovereignty of their country with arms in their hands.

The first armed unit in Indonesia was the People’s Security Agency (Badan Keamanan Rakjat), which was more of a civil defense force than an army. It was formed on August 22, 1945 to maintain security across the newly independent state. When confrontations between Indonesians and the Allied forces (Dutch and British troops) became hostile, the People’s Security Agency was transformed into the People’s Security Armed Forces (Tentara Keamanan Rakyat) on October 5, 1945.

One of the first victories of the newly created Indonesian Army was the victory in the Battle of Ambarawa. The chain of events leading up to the battle kicked off on October 20, 1945, when the Allied forces landed in Semarang to disarm the last remaining Japanese troops and liberate European POWs from internment camps. Initially, the Allies were welcomed in the area due to their promise to respect the sovereignty and independence of Indonesia.

However, many locals were angered when the Allied troops began to free and arm Dutch war prisoners in Ambarawa and Magelang. The situation was further exacerbated by the attempts of the Allies to disarm members of the Indonesian Armed Forces. Indonesian troops retaliated by besieging Allied troops stationed in Magelang, making them flee to Ambarawa.

Indonesians fired the first shots at the Allies in Ambarawa on November 23, 1945 and launched a full-fledged assault on December 11. The Battle of Ambarawa lasted for four days, costing the Allies 2,000 casualties. Indonesian losses were significantly lower, with 100 people killed and 75 people captured and then executed.

To commemorate the Indonesian victory at Abarawa, the anniversary of the final day of the battle, December 15, was declared as Indonesian Army Day. It is marked by military parades, ceremonies and other events honoring the active and reserve personnel of the Indonesian Army, as well as army veterans. Indonesian Army Day should not be confused with Indonesian Armed Forces Day, observed on October 5.