'Strike' was the Allied final offensive in Tunisia by Lieutenant General K. A. N. Anderson’s Allied 1^st Army to defeat Generaloberst Hans-Jürgen von Arnim’s Heeresgruppe 'Afrika' (Generale d’Armata Giovanni Messe’s 1^st Army and General Gustav von Vaerst’s 5^th Panzerarmee) in its final lodgement around Bizerte and Tunis (6/13 May 1943).

The operation was planned by General the Hon. Sir Harold Alexander’s Allied 18^th Army Group as successor to 'Vulcan', and its main task was entrusted to Lieutenant General B. G. Horrocks’s British IX Corps 1, which was to use its two infantry divisions to break through the Axis defences in front of Massicault, some 25 miles (40 km) to the south-west of Tunis, so that the 6^th and 7^th Armoured Divisions could exploit into the Axis rear.

As a preliminary to this move, Lieutenant General C. W. Allfrey’s British V Corps (Major General W. E. Clutterbuck’s 1^st Division, Major General H. A. Freeman-Attwood’s 46^th Division and Major General V. Evelegh’s 78^th Division) was to take the Djebel Bou Aoukaz and so provide a left-flank guard for the IX Corps, holding back one division for exploitation. And at the same time, in the north of the Allied 1^st Army’s sector, Major General Omar N. Bradley’s US II Corps 2 was to take the high ground to the east and west of Chouigui, the crossings over the Medjerda river at Tebourba and Djedeida, and then Bizerte, while in the south of the Allied 1^st Army’s sector Général de Corps d’Armée Marie Louise Koëltz’s French XIX Corps d’Armée 3 was to take the Djebel Zaghouan.

Alexander emphasised that the main objects of the operation were to take Tunis and to trap in northern Tunisia (well away from the Axis embarkation points on the Cap Bon peninsula) as great a part as possible of the Axis forces, and this could only be achieved by passing the 6^th Armoured Division and 7^th Armoured Division through the British 4^th and Indian 4^th Divisions on 6 May so that they could take the high ground some 6 miles (9.5 km) west of Tunis and so prevent the Axis forces from developing the anti-tank defence that would provide a narrow escape corridor to the south-east.

The necessary redeployments had been completed by the night of 5/6 May. Anderson had also arranged for a dummy concentration of tanks near Bou Arada on the IX Corps' front in order to deflect attention from the arrival of the 7^th Armoured Division in the Medjez sector, and thereby achieved a considerable measure of surprise about the size of the armoured force when the attack began.

The offensive began as planned on 6 May but, despite progress, failed to achieve the speed desired by Alexander. Degraded by months of fighting without rest or even adequate reinforcement of men and replacement of worn-out equipment, the Axis forces disintegrated as an army group but continued to offer determined resistance on the basis of individual formations. von Arnim was no longer in the position of being able to exercise control, but in the north the 5^th Panzerarmee fell slowly back under pressure of the II and IX Corps toward Bizerte and Tunis (along the line linking Tebourba, La Mohammedia and the Djebel Oust), while in the south General Hans Cramer’s Deutsches Afrikakorps (with Generalleutnant Friedrich Freiherr von Broich’s 10^th Panzerdivision and Generalmajor Josef Schmid’s Division 'General Göring' under command) fell back before the V and XIX Corps toward the Cap Bon peninsula along the line between the Djebel Oust and Zaghouan).

At the eastern end of the Axis line, along the Gulf of Tunis coast, the 1^st Army held its positions against General Sir Bernard Montgomery’s comparatively inactive British 8^th Army and ensured that the Cap Bon peninsula was in Axis hands for the planned evacuation. Though Messe was not told of the decision, von Arnim and von Vaerst had no intention of seeking to hold either Bizerte or Tunis, where the port installations and other facilities were destroyed on 6 May, just one day before these cities fell to the 9^th Division and 7^th Armoured Division respectively.

The Axis defence was now split into pockets, but still continued to fight doggedly against the rampant Allied forces even though they could not hope to halt the Allied progress. On 9 May von Vaerst and the remnants of the 5^th Panzerarmee surrendered to the II Corps, and the area of Tunisia to the north of the capital was in Allied hands, leaving two Axis groupings (named Armeegruppe 'von Arnim' and Armeegruppe 'Messe' on 11 May) holding out against the 1^st and 8^th Armies respectively.

On 12 May von Arnim and Messe surrendered separately, and the North African campaign of World War II was over. Some 250,000 Axis prisoners were taken, and among the 1^st Army’s booty were some 600 undamaged Axis aircraft abandoned for lack of fuel, whose unavailability (together with that of ammunition) had bedevilled the final resistance of Heeresgruppe 'Afrika'. The Axis forces had also lost at least 50,000 men killed and at least 1,045 aircraft destroyed in the period between 17 November 1942 and 13 May 1943, while the Allies had suffered 76,020 casualties and lost 849 aircraft destroyed.

The Allied casualty list include those of the 1^st Army from 8 November 1942 and the 8^th Army from 9 February 1943. The British and commonwealth losses were 38,360 men (6,233 killed, 21,528 wounded, and 10,599 missing), those of the Free French totalled 19,439 men (2,156 killed, 10,276 wounded and 7,007 missing), and those of the US forces amounted to 18,221 men (2,715 killed, 8,978 wounded, and 6,528 missing).