The Uprising in Serbia was initiated in July 1941 by the Communist Party of Yugoslavia against the German occupation forces and their Serbian quisling auxiliaries in the Territory of the Military Commander in Serbia. At first the Yugoslav Partisans mounted diversions and sabotage and attacked representatives of Milan Aćimović's quisling administration. In late August some Chetniks joined the uprising and liberated Loznica. The uprising soon reached mass proportions. Partisans and Chetniks captured towns that weak German garrisons had abandoned. The armed uprising soon engulfed great parts of the occupied territory. The largest liberated territory in occupied Europe was created by the Partisans in western Serbia, and was known as the Republic of Užice. Rebels shared power on the liberated territory; the center of the Partisan liberated territory was in Užice, and Chetniks had their headquarters in Ravna Gora.
As the uprising progressed, the ideological rift between the two factions became more and more obvious. On one side the Chetnik detachments considered themselves loyal to the royal government-in-exile and fought for the restoration of pre-war order. On the other side, Partisans favored the introduction of socialism and the post-war reorganization of Yugoslavia on a federal basis. The Chetnik leader Dragoljub Mihailović abandoned the uprising in late October and entered into negotiations with the quisling government and the Germans in order to destroy the rival Partisans.
The Germans soon gathered a large force and quelled the uprising using mass terror, but the remaining Partisan forces crossed into Bosnia, where they formed the 1st Proletarian Brigade. After the collapse of the uprising, the Territory of the Military Commander was largely pacified until the return of the Partisans and the Belgrade Offensive in the second half of 1944. Meanwhile, the Chetniks became even more reluctant to fight against the Germans, and engaged in anti-Partisan operations and open collaboration. Nevertheless, Mihailović was able to establish himself as the sole legitimate representative of the Yugoslav government-in-exile, and ordered that all resistance forces should fight under his command.
Background
Hitler believed that with the occupation of Yugoslavia the country was liquidated as an independent state. The Kingdom of Yugoslavia was divided between Nazi Germany, Italy, Hungary and Bulgaria, while in the territory of present-day Croatia and Bosnia and Herzegovina, the Independent State of Croatia was proclaimed. Occupiers plundered possessions and took some 350,000 Yugoslav soldiers prisoner. The largest part of Serbia was organized into the Territory of the Military Commander in Serbia and as such it was the only example of a military regime in occupied Europe. The Germans chose Milan Aćimović as head of the quisling Commissary Government.
Preparations for the uprising
Communists
Preparations for the uprising by the Communist Party of Yugoslavia began after the May consultation held in Zagreb on 4 May 1941. The Military Committee of the Provincial Committee of the Communist Party for Serbia was formed in mid-May. On 13 May 1941, Josip Broz Tito sent a message to the Comintern stating that the Yugoslav communists were preparing for an uprising that would commence when Germany attacked the Soviet Union. The Central Committee of the Communist Party of Yugoslavia arrived in Belgrade in late May, and this was of great importance for the development of the resistance. After their arrival, the Central Committee held conferences with local party officials.
The German invasion of the Soviet Union, Operation Barbarossa, was launched on 22 June 1941. Before the invasion, the Germans withdrew the majority of their troops from Serbia, leaving three weak divisions in Serbia (the 704th, 714th and 717th Infantry Divisions) and one weak division (the 718th Infantry Division) in the Independent State of Croatia. The majority of these divisions were made up of older soldiers from Austria. Communist sympathisers in Srđan Budisavljević's Ministry of the Interior in Dušan Simović's government, such as Janko Janković, destroyed files on communists held in prewar police archives. So when mass arrests of communists began after the launch of Barbarossa, few records were available for the Gestapo to use. The communists then considered that all the requirements for the uprising were met.
The entrance of the USSR into the war strengthened the hope of the Serbian people, who traditionally saw Russia as protector of Serbia, as well as optimism that the war would be over soon. Dragomir Jovanović recorded that on 22 June the atmosphere in the streets was similar to the atmosphere of during the coup on 27 March. In Mačva peasants pulled out stakes from haystacks fearing that Soviet paratroopers would impale themselves by falling on them. In Belgrade, observers were posted on a tall building to report the arrival of Soviet aircraft. In Banat, medical groups were formed to help paratroopers.
Decisions for a struggle in Serbia were issued on June 23, 1941 at the meeting of the Provincial Committee for Serbia, which was attended by Aleksandar Ranković, Spasenija Babović, Đuro Strugar, Moma Marković, Ivo Lola Ribar, Blagoje Nešković, Vukica Mitrović, Mirko Tomić, Miloš Matijević, Ljubinka Milosavljević, Vasilije Buha and Milovan Đilas. At the meeting, party instructors for certain parts of Serbia were decided. For the upcoming struggle, the communists had to hasten the forming of armed groups and collecting weapons and medical supplies. After the meeting, instructors went to their designated areas. By the end of June, Moma Markovic held meetings with district committees in Jagodina, Niš and Zaječar, Mirko Tomić was in charge of Kruševac, Vasilije Buha went to Niš, Milan Mijalković went to Užice and Čačak, Miodrag Ivković to Šabac. Petar Stambolić operated in the Pomoravlje area and Miloš Minić in the Valjevo area. Several local detachments were formed numbering dozens of partisans. Significant amounts of weapons and ammunition were collected.
The Supreme Headquarters of the National Liberation Army of Yugoslavia was established on June 27. Josip Broz Tito was chosen as Supreme Commander. Other members were: Milovan Đilas, Edvard Kardelj, Ivan Milutinović, Aleksandar Ranković, Rade Končar, Franc Leskošek, Sreten Žujović, Ivo Lola Ribar and Svetozar Vukmanović. On July, in the home of Vladislav Ribnikar on Dedinje a session of the Central Committee was held. Present were Tito, Ranković, Milutinović, Đilas, Ribar, Vukmanović and Žujović. A decision was made to begin sabotage and small attacks on German and quisling forces. The Supreme Staff for Serbia was established, with Žujović, Filip Kljajić, Branko Krsmanović, Nikola Grulović and Rodoljub Čolaković as members. This date was later celebrated in socialist Yugoslavia as Fighter's Day.
On July 5, a communist party proclamation appeared that called upon the Serbian people to struggle against the invaders. The Serbian people were reminded of their glorious past, and called to side with "invincible Slavic Russia" headed by Stalin, the greatest son of Russian people. Communists pointed out time had come for an armed struggle against invaders, urged people to organize partisan detachments, set fire to factories and warehouses, destroy railroads and communications, organise hiding of wheat, etc.
Chetniks
Yugoslav Army colonel Dragoljub Mihailović avoided falling into German hands during the invasion. He and his followers hid on the Ravna Gora plateau on Suvobor mountain, arriving on 13 May. It was an isolated area, with weak German presence and influence, and an intact local administration and gendarmerie. During the first months at Ravna Gora, Mihailović tried to come into contact with other officers who had also avoided capture or formed their own detachments, developed an intelligence network, came into contact with the government-in-exile and won local officials to his cause. With their help, Mihailović created lists of reservists and conscripts he would mobilise. The only civilians that were included in his organisation were members of the Serbian Cultural Club, such as Dragiša Vasić and Stevan Moljević.
Mihailović believed that the war would not end soon. He made his first public appearance at a village fair in Tometino Polje on 28 June, where he announced to the gathered people that preparations for armed combat were in place, but the moment for its beginning hadn't yet come.
Resistance begins
Western Serbia was chosen as the base for the uprising, due to its forests and hilly terrain, and a population which had provided strong resistance to invading Austrian forces in World War I. The first Partisan and Chetnik detachments were formed in the Valjevo area.
For the beginning of the uprising the Rađevina partisan detachment took armed action on 7 July 1941 in Bela Crkva near Krupanj. In Bela Crkva the traditional Ivanjdan midsummer village fair was held. A group of fifteen partisans, led by commander Miša Pantić and political commissar Žikica Jovanović Španac gathered people and called them to join in the fight against the German invaders. Speeches were given by Pantić, a doctor from Valjevo, and Jovanović, a journalist from Valjevo and combatant from the Spanish Civil War. Gendarmes Bogdan Lončar and Milenko Braković tried to break up the gathering, forbidden under the military occupation. The partisans opened fire and killed both gendarmes.
Spread of the uprising
The uprising spread from western Serbia to other parts of Serbia. During July and August many Party and SKOJ proclamations that called for armed struggle were printed. Communist groups cut communication lines along railways between Niš and Leskovac. The main power line of Radio Belgrade was cut already on 4 July. Saboteurs in Belgrade set fires on German trucks, garages and trains.
The Commissariat of Interior registered 220 incidents of sabotage in July. Attacks were carried out on police and gendarmerie stations, seats of local governments, rail lines. The village of Valjevska Kamenica was liberated on 22 July. German representative Felix Bender reported to Minister for Foreign Affairs that various groups of "determined communists consists of 60–100 members, who, partially well armed... carries out terrorist acts toward Serbian people, take or kill Serbian officials, make sabotages". Bender mentioned killings of German soldiers, attacks on German trains, trucks, and sabotage of military installations. He also reported that the gendarmerie inflicted losses on communists, but suffered losses as well.
Chetniks join the uprising
When the organized partisan struggle begun, a few ex-Army commanders, originally without Mihailović's approval, carried by the wave of the uprising, took part in combat. Mihailović didn't want to start his uprising, preferring to wait and build up his forces, waiting for a favourable moment. He thought that Germans were stronger in every way and resistance was futile and counter-productive. Participation of Chetnik forces in the uprising was largely forced by fear that the partisans would gain influence among the Serbian people. Former officers couldn't stand to watch how young boys and laymen from ranks of teachers, students, workers and peasants were waging battles. This was particularly true of officers who were compromised by their poor performance during the Axis invasion four months earlier and whom civilians considered incompetent cowards.
In late August Mihailović ordered the creation of Chetnik detachments, made up of recruits 20–30 years old. Their assignment would be to take power at the moment of popular uprising. Mihailović proclaimed himself the legitimate representative of the Yugoslav Royal Army and, on basis of Yugoslav law, demanded the enlistment of reservists 30–40 years old. These Chetnik units had an assignment to prevent pillaging and unnecessary violence, and at the same time, the actions of "destructive elements" (Communists).
At the end of August the first contacts were made between Partisans and Chetniks. Already on August 25, an agreement on joint attacks had been made by the commander of the Podrinje Partisan detachment and Captain Dragoslav Račić, a commander of the Cer Chetnik detachment. Joint Partisan-Chetnik actions against German forces came to the fore during taking of Krupanj and Gornji Milanovac, the battle of Šabac and the sieges of Valjevo and Kraljevo.
Battle of Loznica
Chetnik insurgents launched a surprise attack on the occupied town of Loznica on the morning of 31 August 1941, after the Germans refused the invitation to surrender sent by courier the previous night. Fighting for Loznica was the largest armed conflict with the Germans in occupied Yugoslavia until then.
Capture of Banja Koviljača
Banja Koviljača was captured in a battle fought between 1 and 6 September 1941 between allied forces of Chetniks and Partisans on one side and German forces garrisoned in occupied Banja Koviljača (now Western Serbia) and Ustashe relief forces from Bosnia (then in NDH) on the Axis side. The battle took place soon after Chetniks captured Loznica on 31 August 1941. The attack on the German outpost in Banja Koviljača was the first major battle between Serb rebels and German forces by the end of the invasion of Yugoslavia. The action of Chetniks against the occupying German forces garrisoned in Loznica and Banja Koviljača was organized in a period of Partisan-Chetnik collaboration. The Battle of Banja Koviljača was the first battle where Chetniks and Partisans were allied against Axis forces.
Battle of Krupanj
After three days of fighting, Krupanj was liberated on September 3, 1941 by the Valjevo Partisan detachment and Chetniks led by Orthodox priest Vlada Zečević and his lieutenant Ratko Martinović. Zečević, Martinović and bulk of the Chetniks later joined the partisans.