The battle of Gabes or Wadi Akarit (6-7 April 1943) saw the Eighth Army quickly force their way past an improved defensive line occupied by the Axis forces after their retreat from the Mareth Line.
After their retreat from Libya Rommel's men had occupied the Mareth Line, a defensive position that had originally been built by the French to defend against a possible Italian invasion of Tunisia. They held this position from 15 February, and spent some time strengthening its defenses. Montgomery planned an attack on both flanks (battle of the Mareth line, 20-28 March 1943). By this point Rommel had been replaced as commander of his army by the Italian General Messe, and Panzer Army Africa had been renamed the First Italian Army. The attack on the coastal flank had some early successes, but soon ran into difficulties and it became clear any further progress there would be costly. Fortunately the New Zealanders on the left flank had reached a position from where they could outflank the Axis right. Montgomery decided to switch his main effort to that flank. This attack began on 26 March and by 28 March the Axis forces were in full retreat. They didn’t pull back very far. The last strong defensive position before the Tunisian plains was the Gabes Gap. This was a 12-15 mile wide gap between the Chott el Fedjadj (an area of marshes and lakes) and the Wadi Akarit, which ran to the coast.
The Italians had already spent some time digging in in this position, which was shorter than the Mareth Line, and more difficult to outflank. However it wasn't as well protected by natural defences. The Wadi Akarit was deep and wide near the coast, but faded away inland. The inland end was protected by some hills, but there were gaps in the hills. The Italians had dug an anti-tank ditch on the weaker western end of the line and had placed minefields in the gaps in the hills. The new line was defended by the Italian Saharan Group and the German 164th Light Division on the right, the Pistoia, Spezia and Trieste divisions in the centre and the 90th Light Division and Young Fascist division on the left, near the coast. 15 Panzer Division was in reserve, but 10 Panzer, 21 Panzer and the Centauro division had been forced to move to the north-west to try and stop an American advance from El Guettar (see Operation Wop for more details). The Wadi Akarit position was vulnerable to being outflanked from El Guettar, but also further north from Fondouk Pass. The next defensive position for the Axis forces was at Enfidaville, north-east of Fondouk, so the Allied troops were in a very threatening position.
After considering a number of plans Montgomery decided to use the 4th Indian Division, 50th Infantry and 51st Infantry Divisions to attack the Wadi Akarit, to be supported by the 2nd New Zealand Division. Once the position had been broken, 7th Armour Division would break out to the west while another force would advance up the coast to capture the airfields at Mezzouna.
The first troops to attack were the 4th Indian Division, late on 5 April. They infiltrated into the Axis lines in the hills, and by midnight were engaged with the defenders. The main attack began at 0400 hours on 6 April. It was supported by a heavy artillery bombardment. 50th Division made slow progress (having suffered heavy losses at Mareth), but 51st Division captured the Djebel Roumana and cleared two routes through the Axis minefields and across an anti-tank ditch. Messe moved 164 Light Division from his right to reinforce his centre, and in the afternoon he orderd 15 Panzer to reinforce the Trieste division position, where the biggest danger had developed. 10 Panzer and 21 Panzer were ordered to move back from the El Guettar front. These arrived before Montgomery's men were ready to move again. This also gave Messe time to set up a number of 88mm guns to block any move from the Djebel Roumana. Faced with this obstacle it was decided to delay the next attack until the morning of 7 April, when it could be supported by a heavy artillery bombardment.
By that time the Axis forces had already gone. Messe's commanders reported that they didn’t think they could hold on if attacked again, and by 1700 hours he told von Arnim that the position couldn't be held for another day. At 2000 hours von Arnim ordered the motorised units to retreat back towards Enfidaville, while the less mobile infanty were ordered to walk north. On 7 April the British were able to begin their pursuit, and around 7,000 prisoners were taken.
The Axis retreat permitted Montgomery to carry out his planned two-pronged advance. XXX Corps was sent up the coast, while X Corps was sent inland. On the evening of 7 April an armoured car from the 8th Army met up with a patrol from the US 1st Armored Division, advancing down the road from Gafsa to Gabes. The two Allied armies in North Africa were now in direct contact, and the Germans and Italians were trapped. The breakout at Fondouck failed to progress quickly enough to trap Messe's mobile forces, but the entire southern side of the Axis position had collapsed.
Montgomery's final attack in North Africa came at Enfidaville (19-21 April 1943), a preliminary operation before Operation Vulcan (22-28 April 1943), the start of First Army's final attack on the Tunisian bridgehead.