Battle of Ambarawa

Semarang offensive
Part of the Indonesian National Revolution

British forces in Ambarawa set a village ablaze in retaliation for harboring Indonesian nationalists, 1945.
Date20 October - 16 December 1945
(1 month, 3 weeks and 5 days)
Location
Result
  • Indonesian victory
Territorial
changes
Semarang Regency and Magelang is fully recaptured by Indonesian forces.
Belligerents
 Indonesia
Commanders and leaders
Col. Soedirman (Leader of People's Security Army, Division V/Banyumas)
Lt. Col. Isdiman 
Lt. Col. Gatot Subroto (Division V/Purwokerto)
Lt. Col. M. Sarbini (Central Kedu Regiment)
Maj. Sarjono (Battalion VIII Division III/Surabaya)
Maj. Soeharto (Battalion X Division IX/Yogyakarta)
Brigadier R. G. Bethell
Units involved
Strength
10,000+ (Ambarawa) Unknown
Casualties and losses
2,000 killed 100 killed (Ambarawa)

The Semarang offensive is composite of the Battle of Ambarawa (20 October–15 December 1945; 55 days), Magelang offensive (26 October–15 December 1945; 49 days), Battle of Ungaran or Ungaran offensive, and Semarang offensive proper (Indonesian: Palagan Ambarawa). This major battle took place between the recently created Indonesian Army and the British Army with the Dutch forces that occurred between 20 October 1945 and 2 March 1946 in Semarang city, Semarang Regency, and Magelang Regency in Central Java, Indonesia. Perhaps the most successful Indonesian offensive of the Indonesian Revolution, this offensive tightened British and Dutch control from the Magelang and Semarang metropolitan areas to only Semarang city. In modern times, 15 December is celebrated as the Indonesian National Infantry Day.