Battle of Cape Matapan

The Battle of Cape Matapan was a Second World War naval engagement between British Imperial and Axis forces, fought from 27–29 March 1941. The cape is on the south-west coast of the Peloponnesian peninsula of Greece. Following the interception of Italian signals by the Government Code and Cypher School at Bletchley Park, ships of the Royal Navy and Royal Australian Navy, under the command of the Royal Navy's Admiral Sir Andrew Cunningham, intercepted and sank or severely damaged several ships of the Italian Regia Marina under Squadron-Vice-Admiral Angelo Iachino. The opening actions of the battle are also known in Italy as the Battle of Gaudo.

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.

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