Eastern Southeast Europe (1936–1947 CE): War, Occupation, and Postwar Transformation

Political Upheaval and World War II

Yugoslavia: Axis Occupation and Resistance

During World War II, Yugoslavia initially attempted neutrality but joined the Axis powers in March 1941 under immense German pressure. Public outrage led to a swift military coup, prompting Germany to invade in April 1941. The country was partitioned among Germany, Italy, Hungary, Bulgaria, and newly created puppet states such as the fascist Independent State of Croatia (NDH), led by the Ustaše under Ante Pavelić. Resistance movements quickly emerged, notably the communist Partisans led by Josip Broz Tito, and the royalist Četniks under Draža Mihailović. By war’s end, Tito's Partisans, receiving substantial Allied support, emerged victorious, paving the way for a communist Yugoslavia.

Romania: Alliance with the Axis and Territorial Losses

Under King Carol II, Romania aligned closely with Nazi Germany, seeking to recover territories lost to neighbors. The territorial adjustments imposed by the Second Vienna Award (1940), ceding northern Transylvania to Hungary, and the loss of Bessarabia and northern Bukovina to the Soviet Union significantly weakened Carol’s position. In 1940, the authoritarian General Ion Antonescu took power, joining the Axis invasion of the Soviet Union in 1941. Romania’s participation in the Axis war effort ended with a coup in August 1944, which brought Romania onto the Allied side. Soviet occupation followed, leading Romania firmly into Moscow’s postwar sphere.

Bulgaria: Axis Collaboration and Communist Ascendancy

Bulgaria entered World War II as a reluctant Axis ally in March 1941, largely driven by territorial ambitions in Macedonia and Thrace. Although Bulgaria refused direct participation in military campaigns against the Soviet Union, its collaboration facilitated Axis operations. Communist-led resistance groups gained strength, culminating in a Soviet-supported coup in September 1944, which deposed the pro-Axis government and aligned Bulgaria with the Allies. This set Bulgaria on a path toward Soviet-style communism after the war.

Economic Devastation and Social Change

War-induced Economic Collapse

The war severely disrupted economies across Eastern Southeast Europe, leading to inflation, shortages, and infrastructure destruction. Romania’s oil fields, strategically critical, suffered extensive bombing from both Axis and Allied forces. Agricultural production in Yugoslavia and Bulgaria dramatically declined due to warfare, leading to widespread famine and hardship.

Social Displacement and Humanitarian Crisis

Mass displacements, forced population transfers, and ethnic cleansing significantly altered the demographic landscape. The NDH regime in Croatia carried out genocidal policies against Serbs, Jews, and Roma. Romania’s Jewish and Roma populations also faced deportations and mass murder. Postwar boundary changes and the expulsion of ethnic minorities resulted in further humanitarian crises and lasting demographic shifts.

Postwar Realignments and Communist Consolidation

Yugoslavia: Formation of a Socialist Republic

With Tito’s Partisans in control, Yugoslavia was reconstituted as a communist federation in November 1945, the Socialist Federal Republic of Yugoslavia. Tito distanced Yugoslavia from Soviet control, maintaining a unique position within the emerging communist bloc, setting the stage for future ideological divergences with Moscow.

Romania: Soviet Influence and Communist Domination

Postwar Romania fell under Soviet influence, with the Romanian Communist Party consolidating power through rigged elections, political repression, and the elimination of opposition groups. By 1947, King Michael I was forced to abdicate, and Romania was declared a People’s Republic, solidifying its status as a Soviet satellite state.

Bulgaria: Communist Takeover and Sovietization

Following the 1944 coup, Bulgaria swiftly moved toward a communist government. The postwar Fatherland Front, dominated by communists, executed a series of purges against former political elites and monarchists. In 1946, a referendum abolished the monarchy, and Bulgaria officially became a communist state closely aligned with the Soviet Union.

Cultural and Intellectual Repression

Cultural life was sharply curtailed by wartime censorship and postwar communist policies. Intellectuals, artists, and writers faced increasing state control, with cultural production subordinated to ideological objectives. This period saw severe restrictions on freedom of expression, laying the groundwork for socialist realism as the mandated cultural style.

International Relations and the Onset of the Cold War

From Axis Alliances to Soviet Dominance

The postwar geopolitical order dramatically realigned Eastern Southeast Europe from Axis alliances to Soviet domination. Wartime alliances dissolved, and Soviet control replaced German and Italian influence, setting the stage for the Cold War.

Establishment of the Eastern Bloc

By 1947, Romania and Bulgaria were firmly within the Soviet bloc, their governments closely controlled by Moscow. Yugoslavia, initially aligned with Soviet interests, soon embarked on an independent path, leading to tensions that would become central to Cold War geopolitics in Europe.

Key Historical Developments (1936–1947)

• Axis occupation and resistance movements in Yugoslavia, culminating in Tito’s communist victory.

• Romania’s alignment with Axis powers, followed by territorial losses and subsequent Soviet occupation.

• Bulgaria’s wartime Axis collaboration and swift transition to communism under Soviet influence.

• Economic devastation and humanitarian crises resulting from World War II.

• Postwar communist consolidation across the region and the onset of the Cold War.

Long-Term Consequences and Historical Significance

This period marked a profound transformation in Eastern Southeast Europe, characterized by devastating warfare, mass atrocities, and profound political shifts. The region’s forced integration into the communist bloc reshaped its political, social, and economic structures, with enduring effects on national identities and international alignments that defined its trajectory throughout the second half of the twentieth century.

Sporadic resistance in Croatia, above all among Croatia's Serbs, had begun almost immediately, but it is the communist Partisans under Tito (himself a Croat), who provide the resistance with leadership and a program.

Tito’s Partisans, anxious to gain political legitimacy, demonstrate the strength of their movement by convening the first meeting of the Anti-Fascist Council for the National Liberation of Yugoslavia (Antifasisticko vece narodnog oslobodjenja Jugoslavije, AVNOJ) at Bihac on November 26-27, 1942, to coordinate the military campaigns of Tito's Partisans and the administrative activities of local “liberation committees.”

A committee of communist and non-communist Partisan representatives from all over Yugoslavia, AVNOJ, a self-declared “temporary government,” links the acknowledgment of the ethnic plurality of the peoples of Yugoslavia with the reconstitution of Yugoslavia as a federation.

AVNOJ becomes the political umbrella organization for the people's liberation committees, which the partisans establish to administer territories under their control.

AVNOJ proclaims support for democracy, the rights of ethnic groups, the inviolability of private property, and freedom of individual economic initiative.

Stalin reportedly bars Tito from declaring AVNOJ a provisional government.

At this time, communist forces in Serbia proper are relatively weak.

In occupied Yugoslavia, the participation of non-communists allows a National Liberation Movement to be announced that calls upon all nationalities within Yugoslavia to join the struggle to liberate the country from Axis occupation.

This broad appeal wins support for the Partisans from a populace grown weary of ethnic hatreds.

The Germans and Italians, fearful that a powerful resistance force might encourage the Allies to invade the Balkan Peninsula, lead seven major offensives against the PLA in 1943.

The Partisans, fearing that an Allied invasion will benefit the Cetnici, attack Mihajlovic’s forces.

In March, the Partisans outmaneuver the German army and defeat the Cetnici decisively in Herzegovina and Montenegro.

The Partisans find themselves surrounded in May, however, by German, Italian, Bulgarian, and NDH forces, who launch a final crushing attack.

Through fierce combat, the Partisans escape encirclement in Herzegovina by forcing an exit up the Sutjeska Gorge.

The battle of Sutjeska, a turning point in the fortunes of the Partisans, is of first importance in persuading the Allies to switch their support from the royalists to the communists.

After Tito's headquarters survive bruising Axis operations from January to June (particularly in the battles of Neretva and Sutjeska), the Western Allies recognize Tito as the leader of the Yugoslav resistance and oblige the London government-in-exile to come to terms with him.

Anglo-American and Soviet arms and equipment henceforth are supplied in ever-increasing amounts.

Montenegro becomes a relatively safe haven for Tito's Partisan forces after the fall of Italy in 1943.

The communist-led Slovene National Liberation Front joins Tito's Partisans in proclaiming a new Yugoslavia in November 1943.

At AVNOJ assumes greater legislative and executive functions—and elects a central National Liberation Committee, which becomes virtually a provisional government—at its second session at Jajce on November 29–30, 1943, which includes representatives of various ethnic and political groups.

Tito is proclaimed marshal of Yugoslavia and prime minister, and a plan is adopted for a postwar reorganization of the kingdom into a federation of six equal republics.

Further, AVNOJ issues a declaration forbidding King Petar to return to the country until a popular referendum has been held on the status of the monarchy.