The Ustaše Militia (Croatian: Ustaška vojnica) was the military branch of the Ustaše, established by the fascist and genocidal regime of Ante Pavelić in the Independent State of Croatia (NDH), an Axis puppet state established from a large part of occupied Yugoslavia during World War II.

The militia went through a series of re-organisations during its existence, expanding to include all armed elements of the NDH government outside of the Croatian Home Guard, Navy, and Air Force.

The Ustaše militia was created on 11 April 1941 when Marshal Slavko Kvaternik appointed a separate staff to control the various volunteer armed groups that had risen spontaneously throughout the NDH as the Yugoslav Army collapsed in the face of the Axis invasion.

[1] However, some of the groups that formed early were irregular or "wild" Ustaše units that were not included in the formal organisation, which initially numbered 4,500.

[2] Both formal and irregular units were soon involved in atrocities against Serbs, Jews, Gypsies, and all alleged and actual opponents of the Ustaše regime.

Whilst Pavelić was its titular commander-in-chief, he exercised no practical control over its military operations, as Ustaše formations and units in the field were placed under command of Home Guard or Axis forces.

[5] It also included the small Volksdeutsche militia (German: Einsatzstaffel der Deutschen Mannschaft, EDM), which was created in July 1941 and grew to 1,500 regular and 1,200 reserve troops by June 1942.

[6] In August 1941, the Ustaše Surveillance Service (Ustaška nadzorna služba) was created to combat anti-Ustaše activities throughout the NDH.

The government-controlled press and the state officials encouraged these poorly organized and very aggressive groups to fight enemies of the regime.

After mass crimes against Serb populace committed by Ustaše during the Summer months of 1941, the regime decided to blame all the atrocities to the irregular Ustaše - undisciplined, uncontrolled and paid for their service only with the booty; authorities even sentenced to death and executed publicly in August and September 1941 many of them for unauthorized killing and looting against Serbs and Gypsies.

To put an end to Wild Ustasha uncontrolled activities, the central government used some 6,000 gendarmes and some 45.000 newly recruited members of "Domobranstvo" forces.

[8] In late 1941, an Ustaše militia unit known as the Black Legion was formed mostly from Muslim and Croatian refugees from villages in eastern Bosnia, where the Chetniks and Partisans had already committed large-scale massacres.

The Legion, which had a strength of between 1,000 and 1,500 men, created a fierce reputation in fighting against both Chetniks and Partisans, and was also responsible for large-scale massacres of Serb civilians.

[9] The other special force was the Ustaše Defence Brigades, commanded by Vjekoslav Luburić, who quickly gained a reputation for extreme brutality.

[12] In October 1943, the German commander-in-chief in southeastern Europe, Generalfeldmarschall Maximilian von Weichs, made a proposal to the Wehrmacht operations staff which included the merging of the Ustaše militia into the Croatian Home Guard.

[26] In July 1943, the Ustaše Headquarters issued an order to fill the ranks of the new SS Handschar Division with Muslims serving in its army.

Since then, the Croatian Home Guard conscripts were given an option to carry out their obligatory military service in the Ustaše militia units too.

[37] In August 1942, elements of the Ustaše militia, along with Croatian Home Guard and German forces, conducted a major anti-Partisan operation in Syrmia.

Along with German units, they sent thousands of Serb civilians, including women and children, as well as some Partisans, to the concentration camps at Jasenovac, Sisak, Stara Gradiška, and Zemun.