The small town of Odžak is nestled between the Bosna and Sava rivers, in the north of present-day Bosnia and Herzegovina. To the north and east, a handful of villages spread over the plains, while to the south and west a few shallow inclines lead into the foothills of Vučjak Mountain.

Today the town is a quiet place, only worthy of note due to a large Bosnian flag — allegedly one of the biggest ever — that the town’s inhabitants made a few years ago. However, in the spring of 1945, the last battle of World War II in Europe took place in and around the town.

Fought between Yugoslav Partisans and Independent Croatian forces, the Battle of Odžak ended 16 days after the Allies had celebrated victory in Europe. Yugoslav authorities kept the battle secret until 1971.

In April 1941 the Kingdom of Yugoslavia came under attack from all sides by German, Italian and Hungarian forces, who succeeded in defeating the Royal Army in fewer than two weeks. The invaders annexed large swathes of the country. Italy, the German Reich, Hungary and Italian-occupied Albania all gaining considerable territory.

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The majority of what remained became part of the Independent State of Croatia, a new entity led by the collaborationist regime of Ante Pavelić, an old friend of Benito Mussolini. Although it was nominally sovereign, the Independent State of Croatia was a protectorate of Italy — and after 1943, Germany — and for all intents and purposes was a puppet state. Paveli‘s party, the Ustaša Revolutionary Movement, was extremely nationalist, strongly Catholic, anti-Semitic, anti-Communist and anti-Serb.

The Independent State of Croatia raised an army in the form of the Croatian Home Guard, which inherited much of its equipment and personnel from the defeated Royal Army. At its peak at the end of 1943, the Home Guard commanded 130,000 men, although it was beset with endemic desertion from 1942.

A more reliable force was found in the Ustaše Militia, the armed wing of Pavelić’s party. The militiamen gained a reputation as tough combat soldiers, but lacked discipline and were responsible for terrible atrocities, including the operation of some 20 concentration camps. Thousands more Croatian volunteers joined the Wehrmacht and S.S., forming units such as the Croatian 369th Reinforced Regiment, which fought at Stalingrad.

In November 1944 the Home Guard and Militia were unified to form the Croatian armed forces, which got equipment from Germany and then came under German command.

Prior to the outbreak of war, the Yugoslav Communist Party was a relatively small underground organization of around 12,000 members. Their existing resources and structure, coupled with established communication and logistics networks, placed them in a strong position to become the nucleus of the resistance movement that developed following the Axis invasion.

The resistance movement, commonly referred to simply as “Partisans,” began operations on July 4, 1941, and soon grew into an effective fighting force. Any success they achieved in the early years of the war was limited, however, it faced the combined armies of the Axis occupiers, the forces of the Independent State of Croatia, and at times, Serb nationalist irregular formations.

Despite this, the Partisans rapidly evolved from a loose organization of dispersed units that were largely limited to guerrilla warfare, to an army of considerable size capable of conventional operations. In 1942 the Partisan army counted some 150,000 fighters, a figure that grew to 300,000 in 1943, 650,000 in 1944 and grew to an end-of-war total of 800,000.

The Partisans would harass and raid Axis and Ustaša forces, who in response would occasionally launch large offensives to encircle Partisan forces. The Partisans suffered tremendous casualties, and although the Axis forces came close to eliminating the Partisan leadership a few times, they never managed to inflict a serious defeat. It was not until 1943 that the British began offering significant support to the Partisans, and the Red Army wasn’t able to link up with them until the end of 1944.

By 1945 the Partisans had already liberated much of Yugoslavia. Faced with certain defeat and hundreds of thousands of vengeful Partisans, Army Group E of the Wehrmacht began its slow retreat toward Austria. They were followed by thousands of civilians and soldiers of the collaborationist regime, including Pavelić, who entered Austria on May 6.

The battle

The Partisans liberated Sarajevo, the capital of Bosnia-Herzegovina, on April 6, 1945, and continued their pursuit of the retreating German and Croat troops to the north and west, the direction of Odžak. The precise details of what ensued are difficult to verify, as two competing narratives dominate the historiography.

The post-war Yugoslav authorities had an interest in downplaying the events, as it ran counter to their efforts to reconcile the divided country. For Croatian nationalists, exaggerating the disparity in manpower, equipment and casualties inflicted serves to turn the battle into a tale of heroism and sacrifice in the name of independence akin to the Alamo.

What is clear, however, is that a 26-year-old Ustaša commander, Petar Rajkovačić, chose to stay and make a last stand in his hometown, Odžak, rather than attempt the long march to Austria. Estimates of the strength of Rajkovačić’s force vary, from around 1,800 men to 4,000, but historians agree that it was well-equipped, had plenty of ammunition and had time to fortify its positions. With sizeable rivers to the north and east, Rajkovačić could focus his defenses.

Trenches were dug, bunkers built and barbed wire and minefields were laid.

The Partisans initially bypassed the area around Odžak, focussing on harrying the German retreat, but by the middle of April they had encircled Rajkovačić’s position. Initial Partisan efforts to take ground were fruitless, and came at a considerable cost. With no artillery, armor or air support, the Partisans were limited to containing the Ustaša forces and launching probing attacks until they surrendered.

On V.E. Day — May 8, the day Germany capitulated to the Allies — Allied authorities hoped that the defenders of Odžak would follow. Rajkovačić, however, refused to surrender, and on May 9 the Partisans, in a tactic worthy of the trenches of World War I, brought artillery and bombarded the Ustaša positions before launching a disastrous frontal assault, which was met with an Ustaša counter-attack. When the Croatian armed forces surrendered on May 15, Rajkovačić again insisted on fighting on.

The Battle of Odžak remained an attritional contest until May 23, when the Partisan leadership dispatched two squadrons from its newly established air force. The introduction of air power broke the stalemate, and within two days the Partisans broke through the Ustaša lines and captured Odžak – 16 days after World War II had formally ended.

The cost for both sides is in dispute. Some sources claim the Partisans lost around 1,200 fighters, while others contend that up to 10,000 were killed. Historians agree, however, that most of the Ustaša forces — approximately 1,500 men — perished. It wasn’t until 1971 that a Belgrade weekly, NIN,published an article on the battle, revealing a story that until that point had been known only to Yugoslav authorities and the people who witnessed it first-hand.

This article originally appeared on War is Boring.

Image: Wikimedia Commons