The Battle for Monte Cassino
January 12th - June 5th, 1944
Overall command in Italy: General Sir Harold Alexander
The British 8th Army, commanded by General Sir Oliver Leese after Monty left, and the U.S. 5th army, commanded by Lt. General Mark Clark.
Also, French Expeditionary Force, Canadian, Indian, Polish, and New Zealander forces.
The Germans were determined not to give up an inch to the invading Allied forces and had constructed a defensive line 100 miles south of Rome. The Gustav Line, as this defensive position was known, crossed the primary route from Naples to Rome at the Liri Valley. It was topped by the peak of Monte Cassino, which was the premier tactical position of the line. The view from Monte Cassino was perfect for artillery spotters and nearly the entire position could be seen from the top of the peak. The allied advance on Rome would have to break through that line. The pressure was on to quickly break through. Planning on the D-Day offensive was already in full swing and soon, amphibious and other supplies would be rerouted to England for the upcoming offensive. Patton and Montgomery had already been sent to England in preparation of the upcoming invasion of France. So, the Allied commanders decided to break through the Gustav line in winter, despite mountainous terrain and horrible weather.
The offensive took place in three parts. The purpose of the first part was to break through the Gustav line near Cassino, using a combination frontal assault and amphibious flanking attack. The frontal assault on the line was intended to draw German reserves to the Gustav line, leaving the amphibious flanking landing at Anzio free to cut German lines of communication and resupply south of Rome. Once the supply lines of the Germans were cut, a breakthrough at Cassino was going to be easy. The assault commenced on January 12, and, according to plan, pulled the Germans down out of the mountains to defend the line. The amphibious assault on Anzio then proceeded on January 22nd.
However, the landing on Anzio quickly stalled. Major General John Lucas, commander of the U.S. VI Corps that led the assault, focused on holding the beachhead instead of advancing further. The road to Rome was open from the beach, but he had been warned not to "stick his neck out" and try for Rome before he had built up a logistical base on the beach. He couldn't do both at once, so he was trapped on the beach by German reinforcements rushed from all over Europe. Constant counterattacks prevented the VI Corps from getting off the beach, much less creating any sort of havoc behind the Gustav Line. Instead of the flank attack at Anzio taking pressure off of the forces attacking the Gustav Line, the Gustav Line attack had to be pressed to take the pressure off the beachhead at Anzio.
The second battle of Monte Cassino started with the aerial destruction of the Abbey at Monte Cassino. This attack was ridiculous in the extreme. The abbey had incredible historical significance and its destruction caused a massive public outcry. Also, the abbey was probably not even home to any German forces at the time of the attack. Furthermore, even if the air attack had destroyed German forces, there weren't any allied forces capable of taking advantage of the attack. The second attack was began as British and Indian troops attacked the high ground, while New Zealander forces pushed into Cassino itself. The Americans continued to be stranded on the beaches of Anzio, awaiting some form of relief.
Finally, in May, 1944, the Allies brought their full power to bear. The US 5th Army reinforced the beachhead at Anzio while the British 8th Army moved to the Gustav Line. With a coordinated attack on both fronts, the Allies finally forced a breakthrough in the Liri Valley, overwhelming the town of Cassino and capturing Monte Cassino. However, in a final footnote of stupidity, the commander of the 5th Army, Lt. General Mark Clark, let most of the German defenders escape in his mad dash for Rome. True, the Gustav Line was broken and Rome liberated, but most of the surviving German forces at Monte Cassino were left free to fight another day.
After the breakthrough at Monte Cassino and the liberation of Rome, the Italian front would become a footnote to the rest of the war. With the invasion of France and the surrender of Italy, most supplies and material would be heading to the Western front, leaving the Italian front to limp along as best it could until the eventual defeat of Axis forces.