The Anglo–Iraqi War (2–31 May 1941) was a British-led Allied military campaign against Iraq under Rashid Ali, who had seized power during the Iraqi coup d'état (41-4-1, WW2) with assistance from Germany and Italy. The campaign resulted in the downfall of Ali's government, the re-occupation of Iraq by the United Kingdom, and the return to power of the Regent of Iraq, Prince 'Abd al-Ilah, an ally to the United Kingdom.
The Greek capital Athens fell on 27 April, and by 1 June, after the capture of Crete, all of Greece was under Axis occupation. After the invasion King George II fled, first to Crete and then to Cairo. A nominally Greek right-wing government ruled from Athens, but it was a puppet of the occupiers.
The coup was led by four Iraqi nationalist army generals, known as "the Golden Square", who intended to use the war to press for full Iraqi independence following the limited independence granted in 1932. To that end, they worked with German intelligence and accepted military assistance from Germany and Italy. The change in government led to a British invasion of Iraq and subsequent occupation until 1947.
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On 18 April, Britain reacted by landing the Indian 20th Infantry Brigade at Basra, the first elements of Iraqforce. Britain claimed it was entitled to do this under its defence treaty with Iraq. This treaty was essentially dictated by the British without negotiation or agreement before independence was granted to Iraq. It gave Britain unlimited rights to station and transit troops through Iraq without consulting the Iraqi government.
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The Anglo–Iraqi War (2–31 May 1941) was a British-led Allied military campaign against Iraq under Rashid Ali, who had seized power during the Second World War with assistance from Germany and Italy. The campaign resulted in the downfall of Ali's government, the re-occupation of Iraq by the United Kingdom, and the return to power of the Regent of Iraq, Prince 'Abd al-Ilah, an ally to the United Kingdom.
In late March 1941, as British ships of the Mediterranean Fleet covered troop movements to Greece, Mavis Batey, a cryptographer at Bletchley Park, made a breakthrough, reading the Italian naval Enigma for the first time. The first message, the cryptic "Today’s the day minus three," was followed three days later by a second message reporting the sailing of an Italian battle fleet comprising one battleship, six heavy and two light cruisers, plus destroyers to attack the merchant convoys supplying British forces. As always with Enigma, the intelligence breakthrough was concealed from the Italians by ensuring there was a plausible reason for the Allies to have detected and intercepted their fleet. In this case, it was a carefully directed reconnaissance plane.
As a further deception, Admiral Cunningham made a surreptitious exit after dark from a golf club in Alexandria to avoid being seen boarding his flagship, the battleship HMS Warspite. He had made a point of arriving at the club the same afternoon with his suitcase as if for an overnight stay, and spent time on the golf course within sight of the Japanese consul. An evening party on his flagship was advertised for that night but was never meant to take place.
At the same time, there was a failure of intelligence on the Axis side. The Italians had been wrongly informed by the Germans that the Mediterranean Fleet had only one operational battleship and no aircraft carriers. In fact the Royal Navy had three battleships, while the damaged British aircraft carrierIllustrious had been replaced by HMS Formidable.