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(Thursday, May 18, 1944; a Polish flag was raised over the ruins of Monte Cassino at 9:45 a.m.; during the Battle of Monte Cassino, part of the Italian Campaign of World War II) — The Battle of Monte Cassino, a series of four military assaults by the Allies against German forces in Italy during the Italian Campaign of World War II, ended today in Allied victory when the Germans finally abandoned the stronghold at Monte Cassino.

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.

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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.

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On Feb. 15, 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 Jan. 17 and May 18, Monte Cassino and the Gustav Line defences were attacked on four occasions by Allied troops.

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On May 16, 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 kilometres front. A Polish flag and the British flag were raised over the ruins today.

The capture of Monte Cassino resulted in 55,000 Allied casualties, with German losses estimated at around 20,000 killed and wounded.

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