Yugoslavia and the Allies

In 1941 when the Axis invaded Yugoslavia, King Peter II formed a Government in exile in London, and in January 1942 the royalist Draža Mihailović became the Minister of War with British backing. But by June or July 1943, British Prime Minister Winston Churchill had decided to withdraw support from Mihailović and the Chetniks he led, and support the Partisans headed by Josip Broz Tito. The main reason for the change was not the reports by Fitzroy Maclean or William Deakin, or as later alleged the influence of James Klugmann in Special Operations Executive (SOE) headquarters in Cairo or even Randolph Churchill, but the evidence of Ultra decrypts from the Government Code and Cipher School in Bletchley Park that Tito's Partisans were a "much more effective and reliable ally in the war against Germany". Nor was it due to claims that the Chetniks were collaborating with the enemy, though there was some evidence from decrypts of collaboration with Italian and sometimes German forces.

Given the intensity of 'Operation Punishment' and quick collapse of Yugoslav defence, some SOE agents made their own way to Istanbul or the Middle East, while others followed the fleeing Yugoslav government all the way to Montenegrin coast. Their plans to block the Danube and disrupt German oil and grain supplies from Romania by blowing up a large quantity of rock into the Kazan gorge, or sinking cement-laden barges at Greben narrows or the Sip canal mostly failed. In the end, the river was impassable for between three and five weeks without major impact on the enemy.

At the same time, SOE and the British government lost contact with the agents on the ground and it was not until August 1941. when Mihailović's radio signals were picked up by the British naval monitoring station in Malta. In the confusion of the initial reports, received via agents arriving overland to Istanbul, refugees, and Yugoslav Government-in-Exile (YGE) sources about the situation in the country, alleged persecutions and massacres, as well as pockets of resistance, British government had arranged for direct missions to the region. They mostly consisted of British SOE agents, W/T operators and Yugoslav army officers and had a similar brief: "to discover what was happening in Yugoslavia and co-ordinate all forces of resistance there".

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