The Luftwaffe launches its first attacks against British convoys bound for Malta in the Mediterranean.
German aircraft surprise the Mediterranean fleet, which is escorting 3 merchant ships to Greece. 40 Ju-87 Stukas attack them, scoring 6 hits on HMS Illustrious and severely damaging her. HMS Warspite also receive damage. Both ships make for Malta and arrive the next day.
The Cruisers HMS Southampton and HMS Gloucester are attacked by German aircraft in the Sicilian channel. HMS Gloucester receives damage, while HMS Southampton is sunk. British submarine's begin to make attacks German and Italian convoys crossing to Libya.
The Destroyer HMS Hyperion sunk by mine off Cape Bon.
Force H from Malta bombards Genoa, without hindrance from the Italian Navy or Air force.
Stuka's sink a British Destroyer and the Monitor Terror off the North African coast, near Tobruk.
The British submarine, HMS Upholder, sinks the Italian Cruiser Armando Diaz to the southwest of Malta.
The Royal Navy begins escorting British and Commonwealth troop convoys from Egypt to Greece.
German Naval staff complain to the Italians about their lack of effort to intercept British convoys to Greece.
The British Cruiser York, is severely damaged and then beached at Suda Bay in Crete, when it is hit by an Italian motor boat loaded with explosives.
In an attempt to intercept British convoys sailing to Greece, the Italian navy puts a force of 1 Battleship, 8 Cruisers and 9 Destroyers out to sea. However, they are spotted by an RAF flying boat which alerts Admiral Cunningham who orders the Mediterranean fleet to slip anchor and intercept the Italians the next day.
The Italians spot a British convoy escorted by 4 Cruisers and 4 Destroyers and close in. The British ships lure the Italians towards the main body of the Mediterranean Fleet which includes 3 battleships and the Aircraft Carrier HMS Formidable. HMS Formidable launches aircraft which attack and hit the Italian Battleship Vittorio Veneto with a torpedo, although it manages to limp back to Taranto. Later, they also hit the Cruiser Pola which is seriously damaged. The Italians decide to withdraw and detach 2 cruisers and 4 Destroyers to assist the damaged Cruiser Pola. However, the British intercept them and sink the Cruiser Pola and its 2 escort Cruisers Zara and Fiume as well as 2 of the escorting Destroyers. British losses total just 2 aircraft.
Italian naval forces sink the British Cruiser, HMS Bonaventure off Crete.
A British convoy, codenamed 'Tiger', arrives at Alexandria with much needed tanks and aircraft.
The Royal Navy Minesweeper Widnes is sunk by Luftwaffe planes near Suda Bay in Crete.
Royal Navy sinks several small German troop boats, helping to thwart the sea borne invasion of Crete. The Luftwaffe sinks the British Destroyer Juno and damages the Cruiser Ajax, southwest of Crete.
Heavy German air attacks on Crete sink the cruisers Fiji, Gloucester and York and the destroyer Greyhound. The Battleships HMS Warspite and HMS Valiant are damaged, but the Royal Navy manages to break up a German supply convoy.
Luftwaffe sinks two more British destroyers of Crete, Kashmir and Kelly.
The Aircraft carrier Formidable is severely damaged in Mediterranean by Stukas.
During the evacuation of British troops from Crete, a Luftwaffe attack on the cruiser Orion inflicts 200 casualties and sinks British destroyers Imperial and Hereward.
Stukas sink the British cruiser Calcutta off Alexandria.
Vital convoy reaches Malta after two-day battle; HMS Fearless is sunk.
Italian motorboats with 33 Italian naval assault troops attempt to enter Valletta harbour on the island of Malta to attack British ships, but are discovered. All eight boats are sunk with 15 men being killed and 18 taken prisoner.
Royal Navy Surface Force K from Malta annihilates an Italian convoy of seven supply ships and sinks two destroyers.
Aircraft carrier Ark Royal is torpedoed off Gibraltar by U-81 and later sinks.
U-331 (Kplt. Tiesenhausen) sinks the British battleship Barham in the Mediterranean.
Hitler issues Directive No.38 which tasks Kesselring as C-in-C South, with gaining naval supremacy over the area between southern Italy and Libya in order to deny British supplies to Malta and Libya. To assist with this, he was reinforced with Fleiger Korps II, which was transferred from Russia.
The British manage to turn back an Italian convoy, which is taking supplies to Libya, by making it believe that its under threat from the Mediterranean Fleet.
Royal Navy destroyers sink two Italian Light Cruisers off Cape Bon. Both Cruisers were carrying much needed fuel for Panzer Armee Afrika. U-557 sinks the British Cruiser Galatea outside of Alexandria harbour.
Frogmen of the Italian Navy penetrate the port of Alexandria in Egypt and cripple the British battleships HMS Valiant and Queen Elizabeth, along with a destroyer and a tanker. This means that Cunningham had lost all his battleships and could no longer muster a force strong enough to take on the Italian fleet.