The first battle of Cassino (12 January- 12 February 1944) saw the Allies push slowly closer to the main German defensive lines around Cassino (Gustav Line), but at great cost.
The Germans were defending the line of the Rapido and Garigliano Rivers. The Rapido rises in the mountains north of Cassino and flows south-west through the mountains then south in a more open valley past the town and monastery. It then joins with the Liri, which flows into it from the west, and below the junction is called the Garigliano. The Liri valley was the only open ground to the west of the rivers - the upper reaches of the Rapido are surrounded by mountains and the western shores of the Garigliano are overlooked by the Aurunci Mountains. Highway 6, the road from Naples to Rome, went up the Liri valley. The Allied aim was to break into the Liri valley and use it to send their armour towards Rome.
The attack on the Cassino front was only part of the Allied plan for January. On 22 January, ten days after the start of the battle, another Allied force was to land at Anzio, behind the German lines. It was hoped that this force would be able to advance inland to the Alban Hills, to threaten the lines of retreat for the Germans fighting at Cassino.
General Clark planned a three pronged assault. On the right General Juin’s French Expeditionary Force was to capture the high ground north of Cassino. On the left the British were to cross the upper reaches of the Garigliano and take the nearby high ground at Sant Ambrogio. Once this had been done, the US 36th Infantry Division would cross the lower reaches of the Rapido and establish a bridgehead across the river. The US 1st Armoured Division would cross into this bridgehead and then attack down the river. Clark had three main objectives - tie down the German troops already at Cassino, force Kesselring to move reinforcements from Rome to Cassino so they couldn’t be used against the Anzio landings, and break into the Liri valley to join up with the troops advancing from the bridgehead. Before this could be carried out, the Americans needed to take Monte Troccino, the last high ground before the Rapido, a long narrow mountain that ran parallel to the river. However after some fighting to the east of the mountain the Germans decided that it was too vulnerable and pulled out before the American attack began on 15 January.
Very little of the main plan actually worked. The French began their offensive on 12 January, and made some limited progress east of the Rapido. They took Monte Acquafondata, towards the centre of the mountainous block between the Volturno and Rapido valleys, and on 16 January reached Sant’ Elia, on the eastern edge of the Rapido valley, but were unable to make more progress and the offensive was then called off. An attempt to take Monte Santa Croce, further to the north-east up the Rapido, ended in failure after several days of costly battle.
The British attack began on 17 January, when the 5th and 56th Divisions of X Corps managed to get across the Garigliano, pushing back the German 94th Division, one of the weakest units under Kesselring’s command. The attack began with a heavy artillery bombardment, supported by naval gunfire. The 56th Division then crossed in the centre of the line, and came under heavy fire from previously hidden mortars in the hills north of their crossing point. The 5th Division crossed near the estuary, supported by a short range amphibious landing just behind the river. By dawn on 17 January both of these divisions were across the river and their leading brigades had advanced up to a mile.
The 46th Division had less effective artillery support, as most of their targets were hidden from view from the east bank of the rivers. The division was on the British right, close to the junction of the three rivers. Its crossing ended in failure, after the cables linking their rafts and ferries were snapped by the heavy current and scattered downstream. They were thus unable to get onto the Sant Ambrogio heights to the west of the river, and remained pinned down near the river.
The British suffered 4,000 casualties to establish the bridgehead. In order to stop the British attack, Kesselring had been forced to move two divisions to the front (the 90th Panzer Grenadiers from the Adriatic and the 29th Panzer Grenadiers from Rome), and the departure of the Hermann Goering Division to France was delayed, so Clark had achieved one of his three objectives. The Germans were even able to counterattack on the British front, although with limited success.
Despite these failures on the flanks, the attack across the Rapido went ahead as planned, as Clark believed it was the only way to stop the Germans moving troops back to Anzio. The 36th Division attacked on 20 January, but the river and the defences behind it proved to be a formidable barrier. The attack was a costly failure, and was abandoned on 22 January. The division lost 1,681 men in two days.
On the same day the landings at Anzio began. Clark decided to launch a new offensive on the Cassino front, both to keep the Germans from moving troops north and in the hope that if they did the line might be weakened. This time the attack would be on the right of their line, to the north of Cassino town. General Juin’s French Expeditionary Corps (3rd Algerian and 2nd Moroccan Divisions) were to attack around Monte Belvedere, five miles to the north of Cassino and then move south-west towards the village of Piedimonte, five miles to the west of Cassino. On their left the US 34th Division would cross the Rapido north of Cassino, capture the Cassino massif (the high ground north of Monte Cassino itself) and advance south into the Liri Valley somewhere to the west of Cassino, avoiding having to fight for Monte Cassino at all.
This would be a difficult task. Although the Rapido itself could be waded north of the town, the US troops would first have to cross two miles of swampy ground to the east of the river, created when the Germans demolished a dam near Sant’ Elia. They would then have to fight their way through a line of German pillboxes, barbed wire and mines, before then fighting their way up the slopes of the massif. All the time they would be under accurate artillery fire, directed by German observers on nearby high ground, and in particular on Monte Cassino itself. Allied troops soon came to believe that the observers must be in the famous Benedictine Monastery on top of the mountains, founded in 529 by St Benedict. In fact the Germans never posted any troops in the monastery while it was intact, but they didn’t need to - there was more than enough room away from the exclusion zone around the buildings for their observers to work.
The attack began on 24 January. It took two days to get a toehold across the Rapido, but after a week of hard fighting the 34th Division finally had a secure bridgehead across the river and had reached the Cassino massif. One regiment (133rd Infantry) stayed low down on the eastern slopes and attempted to push south towards Cassino town, while two regiments advanced west into the mountains (135th and 168th Infantry Regiments). After two weeks they had reached the next major ridge to the north-west of the Monastery hill, which became known as ‘Snakeshead’, taking the highest point on 4 February. From there they pushed south-east to Hill 445, a minor summit just 400 yards from the monastery. On the right the 168th Infantry reached Colle Sant’ Angelo, from where they could look down onto Highway 6 in the Liri Valley. The Germans counterattacked, and managed to retake both the summit of ‘Snakeshead’ and Colle Sant’ Angelo, narrowly averting an Allied advance into the Liri valley.
The French attack began on 25 January. They took Monte Belvedere and Abate on 26 January (the next set of mountains to the north of Monte Cassino). However their line was uneven, and the Germans still controlled Monte Cifalco, to the east of Monte Belvedere. They counterattacked from there on 27 January, but were unable to take Belvedere. In order to help, a fresh regiment from the US 36th Division (the 142nd Infantry) was fed into the line between the French and the 34th Division. On the German side General von Senger, commander of XIV Corps, threw his reserves, the 90th Panzer Grenadier Division, into the line, and with their help his battered troops were able to hold the top of the ridgeline, preventing the Allies from advancing down into the Liri Valley.
The 133rd Infantry, on the lower slopes also had a difficult task. The Germans had turned the stone houses of Cassino into mini fortresses, and had built steel reinforced bunkers there were effectively artillery proof. The Americans were able to get a foothold in the north of Cassino, but after that could make no more progress. The final American assault came on 11 February, but by now they were outnumbered by the German defenders of Monastery Hill, and the attack was repulsed. By now the 135th and 168th Infantry only had 840 men left, having started the battle with 840.
On 12-13 February the Americans were replaced by the 4th Indian Division, which had been transferred from the Eighth Army Front. The second battle of Cassino came to an end with the Allies having pushed a salient into the German lines, but without achieving any of their main aims.
The respite would only be short. The beachhead at Anzio was now under severe pressure, and Clark had to resume the offensive on the Cassino Front to prevent the Germans from moving reinforcements north. The resulting second battle of Cassino was by far the most controversial of the four battles, and saw the destruction by bombing of the venerable monastery on Monte Cassino without any military benefit that might have justified it.