The Battle of Monte Cassino, also known as the Battle for Rome, was a series of four military assaults by the Allies against Axis forces in Italy during the Italian Campaign of World War II. The objective was to break through the Winter Line and facilitate an advance towards Rome.
In the beginning of 1944, the western half of the Winter Line was anchored by German forces holding the Rapido-Gari, Liri, and Garigliano valleys and several surrounding peaks and ridges. Together, these features formed the Gustav Line. Monte Cassino, a historic hilltop abbey founded in 529 by Benedict of Nursia, dominated the nearby town of Cassino and the entrances to the Liri and Rapido valleys. Lying in a protected historic zone, it had been left unoccupied by the Germans, although they manned some positions set into the slopes below the abbey's walls.
Repeated artillery attacks on assaulting allied troops caused their leaders to incorrectly conclude that the abbey was being used by the Germans as an observation post, at the very least. Fears escalated, along with casualties, and despite evidence, it was marked for destruction. On 15 February 1944, Allied bombers dropped 1,400 tonnes of high explosives, causing widespread damage. Fallschirmjäger forces occupied the area and established defensive positions amid the ruins.
Between 17 January and 18 May, Monte Cassino and the Gustav Line defences were attacked on four occasions by Allied troops. On 16 May, soldiers from the Polish II Corps launched one of the final assaults on the German defensive position as part of a twenty-division assault along a thirty-two-kilometre front. During the final phase of the Battle of Monte Cassino, the first flag raised over the ruins of the Monte Cassino monastery on the 18th of May 1944, at 10.20am was the Polish flag. It was followed by the British flag shortly after. Following this Allied victory, the German Senger Line collapsed on 25 May, and the German defenders were driven from their positions. The final capture of Monte Cassino resulted in over 43,000 Allied casualties, with German losses estimated at around 51,000 killed and wounded. Total Allied casualties for the Cassino campaign, including the Battle for Anzio and the capture of Rome, were over 105,000, while Axis casualties were at least 80,000. The battle has been described as a Pyrrhic victory.
Background
The Allied landings in Italy in September 1943 by two Allied armies, following shortly after the Allied landings in Sicily in July, commanded by General Sir Harold Alexander, the Commander-in-Chief (C-in-C) of the 15th Army Group (later retitled the Allied Armies in Italy), were followed by an advance northward on two fronts, one on each side of the central mountain range forming the "spine" of Italy. On the western front, the American Fifth Army, commanded by Lieutenant General Mark W. Clark, which had suffered many casualties during the main landing at Salerno (codenamed Operation Avalanche) in September, moved from the main base of Naples up the Italian "boot", and on the eastern front, the British Eighth Army, commanded by General Sir Bernard Montgomery, advanced up the Adriatic coast.
Hitler directed Kesselring to hold as much land in Italy as he could, for as long as possible. Kesselring's subordinates preferred withdrawal, but nevertheless prepared defensive positions across the width of Italy, south of Rome.
The progress of Clark's Fifth Army was hindered by challenging terrain, adverse weather conditions, and well-prepared German defences. The Germans were fighting from a series of prepared positions in a manner designed to inflict maximum damage, then pulling back while buying time for the construction of the Winter Line defensive positions south of the Italian capital of Rome. The original estimates that Rome would fall by October 1943 proved far too optimistic.
Although in the east the German defensive line had been breached on the Adriatic front and Ortona was captured by the 1st Canadian Division, the advance had ground to a halt with the onset of winter blizzards at the end of December, making close air support and movement in the jagged terrain impossible. The route to Rome from the east using Route 5 was thus excluded as a viable option, leaving the routes from Naples to Rome, Highways 6 and 7, as the only possibilities; Highway 7 (the old Roman Appian Way) followed along the west coast but south of Rome ran into the Pontine Marshes, which the Germans had flooded.
Highway 6 (the Via Casilina) ran through the Liri valley, dominated at its south entrance by the rugged mass of Monte Cassino above the town of Cassino. Excellent observation from the peaks of several hills allowed the German defenders to detect Allied movement and direct highly accurate artillery fire, preventing any northward advance. Running across the Allied line was the fast-flowing Rapido River, which rose in the central Apennine Mountains, flowed through Cassino (joining the Gari River, which was erroneously identified as the Rapido) and across the entrance to the Liri valley. There, the Liri River joined the Gari to form the Garigliano River, which continued on to the sea.
With its heavily fortified mountain defences, difficult river crossings, and valley heads flooded by the Germans, Cassino formed a linchpin of the Gustav Line, the most formidable line of the defensive positions making up the Winter Line.
In spite of its potential excellence as an observation post, because of the fourteen-century-old Benedictine abbey's historical significance, the German commander in Italy, Generalfeldmarschall Albert Kesselring, ordered German units not to include it in their defensive positions and informed the Vatican and the Allies accordingly in December 1943.
Nevertheless, some Allied reconnaissance aircraft maintained they observed German troops inside the monastery. While this remains unconfirmed, it is clear that once the monastery was destroyed, it was occupied by the Germans and proved better cover for their emplacements and troops than an intact structure would have offered.
First battle
Plans and preparation
The plan of the Fifth Army commander, Lieutenant General Clark, was for the British X Corps, under Lieutenant General Richard McCreery, on the left of a thirty-kilometre (20 mi) front, to attack on 17 January 1944, across the Garigliano near the coast (5th and 56th Infantry Divisions). The British 46th Infantry Division was to attack on the night of 19 January across the Garigliano below its junction with the Liri in support of the main attack by U.S. II Corps, under Major General Geoffrey Keyes, on their right. The main central thrust by the U.S. II Corps would commence on 20 January with the U.S. 36th Infantry Division making an assault across the swollen Gari river five miles (8.0 km) downstream of Cassino. Simultaneously, the French Expeditionary Corps (CEF) led by General Alphonse Juin would continue its "right hook" move towards Monte Cairo, the hinge to the Gustav and Hitler defensive lines. In truth, Clark did not believe there was much chance of an early breakthrough, but he felt that the attacks would draw German reserves away from the Rome area in time for the attack on Anzio (codenamed Operation Shingle) where the U.S. VI Corps (British 1st and U.S. 3rd Infantry Divisions, the 504th Parachute Regimental Combat Team, U.S. Army Rangers and British Commandos, Combat Command 'B' of the U.S. 1st Armored Division, along with supporting units), under Major General John P. Lucas, was due to make an amphibious landing on 22 January. It was hoped that the Anzio landing, with the benefit of surprise and a rapid move inland to the Alban Hills, which command both routes 6 and 7, would so threaten the Gustav defenders' rear and supply lines that it might just unsettle the German commanders and cause them to withdraw from the Gustav Line to positions north of Rome. Whilst this would have been consistent with the German tactics of the previous three months, Allied intelligence had not understood that the strategy of fighting retreat had been for the sole purpose of providing time to prepare the Gustav line where the Germans intended to stand firm. The intelligence assessment of Allied prospects was therefore over-optimistic.
The Fifth Army had only reached the Gustav Line on 15 January, having taken six weeks of heavy fighting to advance the last seven miles (11 km) through the Bernhardt Line positions, during which time they had sustained 16,000 casualties. They hardly had time to prepare the new assault, let alone take the rest and reorganisation they really needed after three months of attritional fighting north from Naples. However, because the Allied Combined Chiefs of Staff would only make landing craft available until early February, as they were required for Operation Overlord, the Allied invasion of Northern France, Operation Shingle had to take place in late January with the coordinated attack on the Gustav Line some three days earlier.
First assault: X Corps on the left, 17 January
The first assault was made on 17 January. Near the coast, the British X Corps (56th and 5th Divisions) forced a crossing of the Garigliano (followed some two days later by the British 46th Division on their right) causing General Fridolin von Senger und Etterlin, commander of the German XIV Panzer Corps, and responsible for the Gustav defences on the south western half of the line, some serious concern as to the ability of the German 94th Infantry Division to hold the line. Responding to Senger's concerns, Kesselring ordered the 29th and 90th Panzergrenadier Divisions from the Rome area to provide reinforcement. X Corps did not have the extra men, and the battle plan remained unchanged. However, there would certainly have been time to alter the overall battle plan and cancel or modify the central attack by the U.S. II Corps to make men available to force the issue in the south before the German reinforcements were able to get into position. As it happened, Fifth Army HQ failed to appreciate the frailty of the German position and the plan was unchanged. The two divisions from Rome arrived by 21 January and stabilised the German position in the south. In one respect, however, the plan was working in that Kesselring's reserves had been drawn south. The three divisions of Lieutenant General McCreery's X Corps sustained some 4,000 casualties during the period of the first battle.
Main attack: II Corps in the centre, 20 January
The central thrust by the U.S. 36th Division, under Major General Fred L. Walker, commenced three hours after sunset on 20 January. The lack of time to prepare meant that the approach to the river was still hazardous due to uncleared mines and booby traps, and the highly technical business of an opposed river crossing lacked the necessary planning and rehearsal. Although a battalion of the 143rd Infantry Regiment was able to get across the Gari on the south side of San Angelo and two companies of the 141st Infantry Regiment on the north side, they were isolated for most of the time and at no time was Allied armour able to get across the river, leaving them highly vulnerable to counter-attacking tanks and self-propelled guns of Generalleutnant Eberhard Rodt's 15th Panzergrenadier Division. The southern group was forced back across the river by mid-morning of 21 January. Keyes pressed Walker to renew the attack immediately. Once again, the two regiments attacked but with no more success against the well dug-in 15th Panzergrenadier Division: the 143rd Infantry Regiment got the equivalent of two battalions across, but, once again, there was no armoured support, and they were devastated when daylight came the next day. The 141st Infantry Regiment also crossed in two battalion strength and, despite the lack of armoured support, managed to advance 1 kilometre (0.62 mi). However, with the coming of daylight, they too were cut down and by the evening of 22 January, the 141st Infantry Regiment had virtually ceased to exist; only 40 men made it back to the Allied lines.
Rick Atkinson described the intense German resistance:
Artillery and Nebelwerfer drumfire methodically searched both bridgeheads, while machine guns opened on every sound ... GIs inched forward, feeling for trip wires and listening to German gun crews reload ... to stand or even to kneel was to die ... On average, soldiers wounded on the Rapido received "definitive treatment" nine hours and forty-one minutes after they were hit, a medical study later found ..."
The assault had been a costly failure, with the 36th Division losing 2,100 men killed, wounded and missing in 48 hours. As a result, the army's conduct of this battle became the subject of a Congressional inquiry after the war.
II Corps try north of Cassino: 24 January
The next attack was launched on 24 January. The U.S. II Corps, with 34th Infantry Division under Major General Charles W. Ryder spearheading the attack and French colonial troops on its right flank, launched an assault across the flooded Rapido valley north of Cassino and into the mountains behind with the intention of then wheeling to the left and attacking Monte Cassino from high ground. Whilst the task of crossing the river would be easier in that the Rapido upstream of Cassino was fordable, the flooding made movement on the approaches each side very difficult. In particular, armour could only move on paths laid with steel matting and it took eight days of bloody fighting across the waterlogged ground for 34th Division to push back General Franek's German 44th Infantry Division to establish a foothold in the mountains.