The siege of Tobruk (17-21 June 1942) was one of the more embarrassing British defeats in North Africa, and helped to reduce Churchill's confidence in General Auchinleck's abilities as a commander.
In 1941 Tobruk had held out for eight months (10 April-16/17 December 1941), after being besieged towards the end of Rommel's First Offensive. At the time the port was surrounded by a strong line of defences, had a strong garrison (30,000 men and air support), and Rommel had been at the end of his supply lines. Early Axis attacks were disorganised affairs that were easily fought off, and by the time Rommel was able to launch a stronger assault the defenders were ready to meet him. The defence of Tobruk became one of the iconic moments of the British war effort. It dominated strategy in the desert in 1941, and the relief of Tobruk was the target of the unsuccessful Operation Brevity and Operation Battleaxe. The siege was finally lifted as a result of Operation Crusader (November-December 1942), and in the aftermath Rommel was forced to retreat out of Cyrenaica, ending the year back at his starting point.
The pattern almost repeated itself early in 1942. Rommel's Second Offensive saw him reoccupy western Cyrenaica, but this time he ran out of steam west of Gazala. This was followed by a lull in the fighting. The British build up their Gazala Line, and both sides prepared for a new offensive. Rommel moved first (battle of Gazala, 28 May-15 June 1942). His initial outflanking move almost ended in disaster, but after some hard fighting the battle ended with the 8th Army in full retreat. The infantry of XIII Corps escaped largely intact, but the armour of XXX Corps was almost totally destroyed.
As the British began to retreat from Gazala, General Auchinleck (commander-in-chief in the Middle East) and General Ritchie (commander of the 8th Army) disagreed on what to do about Tobruk. Ritchie wanted to use XIII Corps to defend the fortress, while XXX Corps defended the frontier and operated a number of small raiding forces to harass the besiegers. Auchinleck didn't want to risk another siege, and instead wanted to hold a line that ran from Tobruk south to El adem and Bir el Gubi, but on 16 June he had to give Ritchie permission to let Tobruk become 'isolated'.
The issue was soon taken out of their hands. Rommel had also suffered heavy losses during the battle, but he pushed his men onto one more effort. On the night of 16/17 June General Norrie had to abandon El Adem, south of Tobruk. Late on 17 June the 4th Armoured Brigade was forced to retreat from Sidi Rezegh, to the south-east of Tobruk. This meant that the nearby railhead and supply base at Belhamed had to be abandoned, as did the base further east at Gambut. Tobruk was now isolated, while the survivors of the army defeated at Gazala retreated across the Egpytian frontier. XXX Corps had to be withdrawn to Marsa Matruh to refit, while XIII Corps was used to defend the frontier.
The defences of Tobruk weren't as solid in 1942 as they had been in 1941. The main reason for this was that large numbers of mines had been lifted and moved to the Gazala line, as had a great deal of the barbed wire. When the crisis developed the port was defended by Major-General H.B. Klopper, who had been appointed commander of the 2nd South African Division on 14 May. Klopper had his own division, 60 Infantry Tanks of the 32nd Army Tank Brigade, the 201st Guards Brigade, the 11th Indian Infantry Brigade, three regiments of field artillery and two of medium artillery, a total of 35,000 men. Tobruk had been a major supply base for the Gazala Line, and as a result was full of stores. However there was little chance of any air support, as the Desert Air Force had been forced to retreat to Sidi Barrani, and there were only fifteen 6-pounder anti-tank guns in the fortress.
Tobruk was fully besieged by 18 June. Rommel decided to attack on the south-eastern side of the perimeter. This was defended by the 2/7th Gurka Rifles nearest to the coast, then the 2/5th Mahrattas and finally the 2nd Cameron Highlands, defending the area up to the El Adem road. 15 Panzer and 21 Panzer were to attack the Mahrattas, while the Trieste and Ariete divisions were to attack the Cameron Highlands.
The attack began with a heavy dive bomber attack early on 20 June. The main attack began at 0800, and by mid morning the two German divisions had pushed the Mahrattas back a mile and a half. Ritchie attempted to held by ordering XIII Corps to attack towards Sid Rezegh, but this was easily repulsed by the German 90th Light Division.
Back at Tobruk the Germans soon broke through the perimeter defences. By 1600 hours they had captured the airfield, and by 1700 hours they had reached the port. Klopper withdrew into the western half of the perimeter, but there was nothing he could do. His men spent the night attempting to destroy the stockpiled supplies, but at 0800 on 21 June he asked for surrender terms. The South African troops in the western perimeter surrendered early on 21 June. Back on the perimeter the undefeated Cameron Highlands and the Gurkhas fought on for the rest of the day, but finally surrendered on the evening of 21 June.
Rommel took 33,000 prisoners at Tobruk, including 19,000 British troops. He also captured 2,000 tons of fuel, 5,000 tons of provisions, 2,000 vehicles and large stockpiles of ammunition. The entire battle of Gazala and siege of Tobruk cost the Germans around 3,360 casualties (at least according to their records), but this did include 300 officers. Rommel was awarded for his success with promotion to Field Marshal.
At the time of the surrender Churchill was visiting Washington, and suffered the embarrassment of having the news broken to him by President Roosevelt. Churchill described the fall of Tobruk as 'one of the heaviest blows I can recall during the war … defeat is one thing, disgrace is another'. The only good news to come from this defeat was that Roosevelt offered to sent 250 new M4 Sherman tanks to the Eighth Army, where they played a major part in the later victory at El Alamein.