the month, when airborne deliveries from Sicily began. Rommel decided to abandon Tobruk and withdraw to Gazala, which led to the relief of Tobruk and the occupation of Cyrenaica. Aftermath Analysis For much of the siege, Tobruk was defended by the 9th Australian Division and other troops. Wavell ordered Morshead to defend the port for eight weeks; the Australians held on for over five months, before being gradually withdrawn during September and replaced by the 70th Infantry Division, the Polish Carpathian Brigade and Czechoslovak 11th Infantry Battalion (East). The fresh defenders held Tobruk until they broke out on 21 November and held open an corridor, unsupported for several days, then captured Ed Duda on 27 November, to link with the advancing Eighth Army, during Operation Crusader. The Tobruk Ferry Service, made up of Royal Navy and Royal Australian Navy warships, played an important role in the defence of Tobruk providing gunfire support, supplies, fresh troops and by ferrying out the wounded. Control of Tobruk was useful to the Allies because it was the only significant port east of Benghazi and west of Alexandria. The supply of Axis troops on the Egyptian frontier could have been eased by sea transport to Tobruk. The siege of Tobruk was the first occasion in the war that German Panzer units had been stopped. The siege of Tobruk was lifted in December 1941 in the course of Operation Crusader. Axis forces re-captured the port on 21 June 1942, after defeating the Eighth Army in the Battle of Gazala. During the course of the siege, two destroyers, three sloops, seven anti-submarine vessels and minesweepers, seven store carriers and schooners, six A lighters and one fast minelayer were sunk, a total of 26 ships. Seven destroyers, a sloop, eleven anti-submarine and minesweeping vessels, three gunboats and a schooner were damaged, a total of 23 vessels. Six Merchant Navy ships and a schooner were sunk and six merchant ships were damaged; a total of 62 ships were sunk or damaged. Casualties The Rats of Tobruk suffered at least there being a small difference in Australian casualty figures quoted in the Australian and British official histories. Most of the Australian garrison withdrew from Tobruk between August and October but others remained in Tobruk for the duration. In Australia in the War of 1939–1945 (1967) the Australian Official History, Maughan recorded 9th Australian Division casualties from including two days before