The first battle consisted of an assault on the Gustav line came on the 17th of January 1944 where attempts were made to outflank the German position. Many of the corps involved never managed to complete the flanking manoeuvre as the meet heavy resistance, due to the excellent defensive positions attained by the Germans who had a commanding view of the area before them. The first assault on the Cassino front of the Gustav line had not been very successful, with only pockets of allied resistance dotted around the surrounding hills and mountains. .
The second battle consisted of an assault on the Cassino front on the 15th of February. On the 14th leaflets were dropped onto the monastery telling the occupants and refugees that the allies had decided to bomb Monte Cassino and surrounding German positions from the air. Son after the monastery was pulverized, its architecture destroyed and left in ruins. What the allies had not expected was that the bombing had turned the monastery into a fortress. After the bombing it seemed likely that there were no Germans in the monastery at the time, furthermore the nearest allied troops were too far away to take advantage of the shock of the bombing. Following the bombing British and Indian troops attacked the high ground, while New Zealanders bludgeoned their way into Cassino itself. While there were some gains, the German grip was not shaken.
The third battle began on the 15th of March in fine weather with another bombing attack. The Germans took shelter under ground ready to emerge and take up defensive positions once the bombing had finished. Despite extraordinary courage of British, Indian and New Zealand troops, the Germans holding the town and high ground still hung on.
The fourth and final battle began in the evening of the 11th of May with an opening barrage of 2000 allied artillery pieces catching the Germans totally by surprise. Within an hour Polish forces were on Calvary Hill, just over 1 km north west of Cassino.