As a part of the Resistance during World War II People's Liberation War of Yugoslavia, the People's Liberation Army of Yugoslavia (NOVJ), a predecessor of JNA, was formed on 22 December 1941 in the town of Rudo in Bosnia and Herzegovina with the establishment of the 1st Proletarian Brigade.

After the liberation of the country from the Axis Powers occupation, that date was officially celebrated as the Day of the Army in the SFR Yugoslavia.

In March 1945, the NOVJ was renamed the Yugoslav Army (Jugoslovenska Armija) and finally on its 10th anniversary on 22 December 1951, received the adjective People's (i.e.

[3] In September 1968, the Territorial Defense (TO) was formed to support the JNA and on 21 February 1974 TO units were subordinated to their provinces or republics.

While parts of the structure changed from 1968 to 1988, the main outlines stayed the same: Plus the Coastal Naval District (Split) – formerly Fourth Army As of July 1979 the International Institute for Strategic Studies estimated the Yugoslav ground forces to include 190,000 personnel (including 130,000 conscripts), eight infantry divisions, seven independent tank brigades, 12 independent infantry brigades, two mountain infantry brigades, one airborne battalion, 12 artillery regiments, six anti-tank artillery regiments, and 12 anti-aircraft artillery regiments.

In 1988 the armies were reorganized into Military Districts or Regions which no longer corresponded to internal borders thereby making it harder for the republics to control their own forces.

In late June 1990, the JNA dissolved the 6th Proletarian Infantry Division and the Zagreb city defence command.

[8] Once considered the fourth strongest army in Europe with 200,000 active troops and 2 million reserves, in 1991, at the outbreak of the Yugoslav Wars the ground forces were organized in four military regions.

Small number of units of the ground and air forces were outside of the military regions directly under General Staff command and control.

The shift to brigade-level organization provided greater operational flexibility, maneuverability, and tactical initiative, and it reduced the possibility that large army units would be destroyed in setpiece engagements with an aggressor.

In the 1980s the ground forces had about 200,000 active-duty soldiers (including 90,000 conscripts) and could mobilize over a million trained reservists in wartime.

During the Ten Day War the JNA performed abysmally as many of the Yugoslav soldiers did not realise they were taking part in a real military operation, rather an exercise, until they came under attack.

Of the soldiers of the 5th Military District, which was in action in Slovenia, in 1990 30% were Albanians, 20% Croats, 15 to 20% Serbs and Montenegrins, 10% Bosniaks, and 8% Slovenes.

Its poor performance in Slovenia and later in Croatia discredited its leadership – Kadijević resigned as defence minister in January 1992, and Adžić was forced into medical retirement shortly afterwards.

Domestic production of the M-84 (an improved version of the Soviet T-72 built under license in Yugoslavia) was providing the army with a late 1970s and 1980s model.

Yugoslav artillery units operated several battlefield missile systems including 160 128 mm YMRL-32 and M-63 multiple-rocket launchers.

The four wheeled BOV-1 armored reconnaissance vehicle could be equipped with six AT-3 launchers to serve as a highly mobile anti-tank platform.

Of both domestic and foreign origin, they included pieces purchased from the United States, Czechoslovakia, Switzerland, and Sweden.

They operated the Soviet-designed SS-C-3 and a truck-mounted, Yugoslav-produced Brom antiship missile which was essentially a Yugoslav variant of the Soviet SS-N-2.

All soldiers wore neckties of the same colors except in summer, when the uniform shirt was worn with an open collar.

Mountain troops wore distinctive stiff field caps with semi-rigid visors and ear flaps.

Full dress uniforms were blue and were worn with a yellow-gold sash belt lined with the appropriate service color.

Cap emblems all included a red star with yellow-gold rays, given distinctive configurations according to branch.