The Danube as a Significant Line of Communication and Strategic Barrier for Serbia and Yugoslavia in the First Half of the Twentieth Century

Abstract

In the first half of the twentieth century, the Danube was extremely important to Serbia and Yugoslavia in two ways. Firstly, it served as a communication line that played a significant role in the economy, especially that of the Kingdom of Serbia. Secondly, it served as a strategic barrier in wartime. The Danube's importance became even more evident during the so-called “Customs War”, or “Pig War” with Austria-Hungary between 1906 and 1911, which resulted in Serbia's economic independence. During the First World War, the Danube was not only a natural obstacle on the Austrian front, but also a strategic communication and supply line for both the Entente and the Central Powers. The control of the river, together with gaining full control of the Belgrade — Niš — Sofia — Constantinople railway line, was the main reason for the joint Austro-Hungarian, German and Bulgarian campaign against Serbia in October 1915. During the campaign, the Germans crossed the Danube in their section of the front line, which at the time was the largest crossing operation of the river in military history. After the First World War, the Kingdom of Yugoslavia gained the largest commercial fleet on the Danube through reparations. Between the two world wars, more than 40 % of Yugoslavian goods were exported along the Danube. In the late 1930s, the Danube’s role in supplying Nazi Germany with raw materials from the Balkans, especially Romanian oil, increased. The only place suitable for sabotage operations to destabilize the supply of the German war machine was the Iron Gate, a narrowing of the Danube at the Yugoslav-Romanian border. The importance of the Danube River was demonstrated during the April 1941 war, when Germany actually attacked Yugoslavia on the night of 5–6 April 1941, capturing the Sip Canal, the most important of the seven canals cut through the Iron Gate Gorge, guarded by the Yugoslav Army. In the Second World War, the Allies bombed many ports on the Danube and German ships carrying oil. Supplies were interrupted by the joint Soviet-Yugoslav offensive, which ended in the liberation of Belgrade. Finally, the largest battle of the Second World War in Yugoslavia, fought by the Red Army and the Yugoslav People's Liberation Army, took place from 11 to 29 November 1944, near the village of Batina, on the right bank of the Danube.