In early 1944, the German forces held a defensive line known as the Winter Line, encompassing the Rapido-Gari, Liri, and Garigliano valleys. The heart of this line was the Abbey of Monte Cassino, strategically positioned to dominate the entrances to the Liri and Rapido Valleys. Despite the German assertion that the abbey would not be fortified, Allied forces suspected its use as a reconnaissance post. Consequently, a decision was made to assault the Abbey.
On February 14th, American bombers unleashed a devastating bombardment of the Abbey, reducing a significant portion of its structure to ruins. However, the German forces, now reacquainted with the potential of the ruins as a defensive position, promptly dispatched thousands of troops to reinforce it.
The capture of the Abbey swiftly became a pivotal moment in the Gustav Line. It was widely regarded as the key to breaching the line and securing Rome. The initial assault commenced on January 17th, with the expectation that the combined efforts of the assault and the Anzio landing would compel the Germans to retreat beyond the city limits. However, after three grueling days of intense combat, it became evident that this objective was unattainable, and the assault concluded in defeat.
The second attempt at capturing the Abbey was undertaken on February 17th. The primary factor in this attempt was the deployment of Gurkahas, renowned for their exceptional mountain combat experience. Unfortunately, this strategy proved equally unsuccessful.
The third attempt to capture Monte Cassino commenced on March 15th, accompanied by a massive bombing and artillery barrage. The New Zealand Division led the assault, but despite intense resistance, it proved no more successful than the previous attempts.
The third and final assault commenced on May 11th, also preceded by a massive bombardment. This time, the attack encompassed the entire length of the line. The US Gift and French Expeditionary forces swiftly achieved most of their objectives. The British XIII Corps successfully deployed tanks to defend against any potential German counterattack. Simultaneously, elements of a Polish army division engaged in combat in the hills above the abbey, encountering fierce resistance from the Germans. However, by May 18th, the Poles had gained the upper hand and were successfully breaking through German lines. Consequently, the German forces recognized the untenability of their position and initiated a withdrawal towards the north.
The cost of capturing Monte Cassino was exceptionally high. The Allied forces suffered 50,000 casualties, while the German forces endured 20,000.