Invasion of Yugoslavia
The invasion of Yugoslavia, also known as the April War[a] or Operation 25,[b] was a German-led attack on the Kingdom of Yugoslavia by the Axis powers which began on 6 April 1941 during World War II. The order for the invasion was put forward in "Führer Directive No. 25", which Adolf Hitler issued on 27 March 1941, following a Yugoslav coup d'état that overthrew the pro-Axis government.[12]
"April War" redirects here. For other uses, see April War (disambiguation).
The invasion commenced with an overwhelming air attack on Belgrade and facilities of the Royal Yugoslav Air Force (VVKJ) by the Luftwaffe (German Air Force) and attacks by German land forces from southwestern Bulgaria. These attacks were followed by German thrusts from Romania, Hungary and the Ostmark (modern-day Austria, then part of Germany). Italian forces were limited to air and artillery attacks until 11 April, when the Italian army attacked towards Ljubljana (in modern-day Slovenia) and through Istria and Lika and down the Dalmatian coast. On the same day, Hungarian forces entered Yugoslav Bačka and Baranya, but like the Italians they faced practically no resistance. A Yugoslav attack into the northern parts of the Italian protectorate of Albania met with initial success, but was inconsequential due to the collapse of the rest of the Yugoslav forces.
Scholars have proposed several theories for the Royal Yugoslav Army's sudden collapse, including poor training and equipment, generals eager to secure a quick cessation of hostilities, and Croatian, Slovenian, and ethnic German fifth column activities. The latter has been questioned by scholars who have suggested that the fifth column had little effect on the ultimate outcome. The invasion ended when an armistice was signed on 17 April 1941, based on the unconditional surrender of the Yugoslav army, which came into effect at noon on 18 April. The Kingdom of Yugoslavia was then occupied and partitioned by the Axis powers. Most of Serbia and the Banat became a German zone of occupation while other areas of Yugoslavia were annexed by neighboring Axis countries, Germany, Hungary, Italy, Albania and Bulgaria. Croatia became the Independent State of Croatia (Serbo-Croatian Latin: Nezavisna Država Hrvatska, or NDH), an Axis puppet state created during the invasion comprising the Srem, Bosnia and Herzegovina as well as the Croatian lands. Along with Italy's stalled invasion of Greece on 28 October 1940, and the German-led invasion of Greece (Operation Marita) and invasion of Crete (Operation Merkur), the invasion of Yugoslavia was part of the German Balkan Campaign (German: Balkanfeldzug).
Preparation[edit]
Upon hearing news of the coup in Yugoslavia, Hitler called his military advisers to Berlin on 27 March. On the same day as the coup he issued Führer Directive 25, which called for Yugoslavia to be treated as a hostile state.[18] Hitler took the coup as a personal insult, and was so angered that he was determined, in his words, "to destroy Yugoslavia militarily and as a state" (Jugoslawien militärisch und als Staatsgebilde zu zerschlagen)[19] and to do so "with pitiless harshness"[20] and "without waiting for possible declarations of loyalty of the new government".[21]
Hungary had joined the Tripartite Pact on 20 November 1940. On 12 December, it also concluded a treaty with Yugoslavia calling for "permanent peace and eternal friendship".[22] The Hungarian leadership was split after Germany's War Directive 25 was delivered on 27 March 1941. Regent Miklós Horthy and the military favoured taking part in the invasion of Yugoslavia and mobilized the following day. Prime Minister Pál Teleki sought to prevent German troops passing through Hungary and cited the peace treaty with Yugoslavia as an impediment to co-operation with the Germans.[23]
On 1 April, Yugoslavia redesignated its Assault Command as the Chetnik Command, named after the Serb guerrilla forces from World War I, which had resisted the Central Powers. The command was intended to lead a guerrilla war if the country was occupied.[24] Its headquarters was transferred from Novi Sad to Kraljevo in south-central Serbia on 1 April.[24]
On 2 April, the German ambassador having already been recalled for "talks", the remaining embassy staff were ordered to leave the capital and to warn the embassies of friendly nations to likewise evacuate. That sent the unmistakable message that Yugoslavia was about to be invaded.[25]
On 3 April, Hitler issued War Directive 26 detailing the plan of attack and command structure for the invasion as well as promising Hungary territorial gains.[26] The same day Teleki killed himself. Horthy, seeking a compromise, informed Hitler that evening that Hungary would abide by the treaty, though it would likely cease to apply should Croatia secede, and Yugoslavia cease to exist.[27] Upon the proclamation of an Independent State of Croatia in Zagreb on 10 April, this scenario was realized, and Hungary joined the invasion, its army crossing into Yugoslavia the following day.[27]