The Battle of Crete (German: Luftlandeschlacht um Kreta, Greek: Μάχη της Κρήτης), codenamed Operation Mercury (German: Unternehmen Merkur), was a major Axis airborne and amphibious operation during World War II to capture the island of Crete.
The battle began on the morning of 20 May 1941, with multiple German airborne landings on Crete; Greek and other Allied forces, along with Cretan civilians, defended the island. After the first day of fighting, the Germans had suffered heavy casualties and Allied troops were confident that they would defeat the invasion.
The next day, through communication failures, Allied tactical hesitation, and German offensive operations, Maleme Airfield in western Crete fell, enabling the Germans to land reinforcements and overwhelm the defensive positions in the north of the island. Allied forces withdrew to the south coast; more than half were evacuated by the British Royal Navy and the remainder surrendered or joined the Cretan resistance. The defence of Crete evolved into a costly naval engagement; by the end of the campaign the Royal Navy's eastern Mediterranean strength had been reduced to only two battleships and three cruisers.
The Battle of Crete was the first occasion where Fallschirmjäger (German paratroops) were used en masse, the first mainly airborne invasion in military history and the first time the Allies made significant use of intelligence from decrypted German messages from the Enigma machine, and the first time German troops encountered mass resistance from a civilian population.
Due to the number of casualties and the belief that airborne forces no longer had the advantage of surprise, Hitler became reluctant to authorise further large airborne operations, preferring instead to employ paratroopers as ground troops. In contrast, the Western allies were impressed by the potential of paratroopers and started to form airborne-assault and airfield-defence regiments.
British forces had initially garrisoned Crete when the Italians attacked Greece on 28 October 1940, enabling the Greek government to employ the Fifth Cretan Division in the mainland campaign. This arrangement suited the British: Crete could provide the Royal Navy with excellent harbours in the eastern Mediterranean, from which it could threaten the Axis south-eastern flank, and the Ploiești oil fields in Romania would be within range of British bombers based on the island.
The Italians were repulsed, but the subsequent German invasion of April 1941 (Operation Marita), succeeded in overrunning mainland Greece. At the end of the month, 57,000 Allied troops were evacuated by the Royal Navy. Some were sent to Crete to bolster its garrison until fresh forces could be organised, although most had lost their heavy equipment. Winston Churchill, the British prime minister, sent a telegram to the Chief of the Imperial General Staff, General Sir John Dill: "To lose Crete because we had not sufficient bulk of forces there would be a crime."
The German Army High Command (Oberkommando des Heeres, OKH) was preoccupied with finalizing preparations for Operation Barbarossa, the invasion of the Soviet Union, and was largely opposed to a German attack on Crete. However, Hitler remained concerned about attacks in other theatres, in particular on his Romanian fuel supply, and Luftwaffe commanders were enthusiastic about the idea of seizing Crete by a daring airborne attack. The desire to regain prestige after their defeat by the Royal Air Force (RAF) in the Battle of Britain the year before may also have played a role in their thinking, especially before the advent of the much more important invasion of the Soviet Union. Hitler was won over by the audacious proposal and in Directive 31 he asserted that "Crete... will be the operational base from which to carry on the air war in the Eastern Mediterranean, in co-ordination with the situation in North Africa." The directive also stated that the operation was to be in May and must not be allowed to interfere with the planned campaign against the Soviet Union. Before the invasion, the Germans conducted a bombing campaign to establish air superiority and forced the RAF to move its remaining aeroplanes to Alexandria in Egypt.
No RAF units were based permanently at Crete until April 1941, but airfield construction had begun, radar sites had been built and stores delivered. Equipment was scarce in the Mediterranean and in the backwater of Crete. The British forces had seven commanders in seven months. In early April, airfields at Maleme and Heraklion and the landing strip at Rethymno on the north coast were ready and another strip at Pediada-Kastelli was nearly finished. After the German invasion of Greece, the role of the Crete garrison changed from the defence of a naval anchorage to preparing to repel an invasion. On 17 April, Group Captain George Beamish was appointed Senior Air Officer, Crete, taking over from a flight-lieutenant whose duties and instructions had been only vaguely defined. Beamish was ordered to prepare the reception of the Bristol Blenheim bombers of 30 and 203 squadrons from Egypt and the remaining fighter aircraft from Greece, to cover the evacuation of W Force, which enabled the transfer of 25,000 British and Dominion troops to the island, preparatory to their relief by fresh troops from Egypt.
The navy tried to deliver 27,000 long tons (27,000 t) of supplies from 1–20 May 1941, but Luftwaffe attacks forced most ships to turn back, and only 2,700 long tons (2,700 t) were delivered. Only about 3,500 trained British and Greek soldiers were on the island, and the defence devolved to the shaken and poorly equipped troops from Greece, assisted by the last fighters of 33, 80 and 112 squadrons and a squadron of the Fleet Air Arm, once the Blenheims were ordered back to Egypt. In mid-May, the four squadrons had about two dozen aircraft, of which only about twelve were serviceable due to a lack of tools and spares. The unfinished ground at Pediada-Kastelli was blocked with trenches and heaps of soil and all but narrow flight paths were blocked at Heraklion and Rethymno by barrels full of earth. At Maleme, blast pens were built for the aircraft, and barrels full of petrol were kept ready to be ignited by machine-gun fire. Around each ground, a few field guns, anti-aircraft guns, two infantry tanks and two or three light tanks were sited. The three areas were made into independent sectors, but there were only eight QF 3-inch and twenty Bofors 40 mm anti-aircraft guns.
On 30 April 1941, Major-general Bernard Freyberg VC a New Zealand Army officer, was appointed commander of the Allied forces on Crete (Creforce). He was Churchill's personal choice, as the British Prime Minister admired his loyalty and the bravery he had shown during the First World War. By May, the Greek forces consisted of approximately 9,000 troops: three battalions of the 5th Greek Division, which had been left behind when the rest of the unit had been transferred to the mainland against the German invasion; the Cretan Gendarmerie (2,500 men); the Heraklion Garrison Battalion, a defence unit made up mostly of transport and supply personnel; and remnants of the 12th and 20th Greek divisions, which had also escaped from the mainland to Crete and were organised under British command. Cadets from the Gendarmerie academy and recruits from Greek training centres in the Peloponnese had been transferred to Crete to replace the trained soldiers sent to fight on the mainland. These troops were already organised into numbered recruit training regiments, and it was decided to use this structure to organise the Greek troops, supplementing them with experienced men arriving from the mainland.
The British Commonwealth contingent consisted of the original 14,000-man British garrison and another 25,000 British and Commonwealth troops evacuated from the mainland. These evacuees were a combination of intact units, composite units improvised locally, stragglers from every type of army unit, and deserters; most of them lacked heavy equipment. The main formed units were the 2nd New Zealand Division, less the 6th Brigade and division headquarters; the 19th Australian Brigade Group; and the 14th Infantry Brigade of the British 6th Division. There were about 15,000 front-line Commonwealth infantry, augmented by about 5,000 non-infantry personnel equipped as infantry and a composite Australian artillery battery. On 4 May, Freyberg sent a message to the British commander in the Middle East, General Archibald Wavell, requesting the evacuation of about 10,000 unwanted personnel who did not have weapons and had "little or no employment other than getting into trouble with the civil population". As the weeks passed, some 3,200 British, 2,500 Australian and 1,300 New Zealander troops were evacuated to Egypt, but it became evident that it would not be possible to remove all the unwanted troops. Between the night of 15 May and morning of 16 May, the allied forces were reinforced by the 2nd Battalion of the Leicester Regiment, which had been transported from Alexandria to Heraklion by HMS Gloucester and HMS Fiji.