World War II History: 20 Most Important Battles of WWII

One of the most audacious operations in the German conquest of Europe was the air assault on the Greek island of Crete, the first action in which paratroopers were dropped in large numbers. Crete was defended by British and Greek forces who had some success against the lightly armed German soldiers jumping out of the sky. However, delays and communication failures between Allies allowed the Germans to capture the vital airfield at Maleme and fly in reinforcements. Once the Nazis gained air superiority, landings by sea followed. The Allies surrendered after two weeks of fighting.

The Battle of Iwo Jima is an iconic event, thanks largely due to Joe Rosenthal’s photograph of the American flag being raised. But military analysts still argue whether the island’s limited strategic value justified the costly action. Twenty thousand Japanese defenders were dug in to an elaborate system of bunkers, caves, and tunnels. The attack was preceded by a massive naval and air bombardment lasting several days covering the entire island. Although outnumbered five to one and with no prospect of victory, the Japanese put up strong resistance and virtually none surrendered. Many positions could be cleared only out by hand grenades and flamethrowers, including the fearsome M4A3R3 Sherman “Zippo” flamethrower tanks.

The Allies invaded Italy in 1943 but by 1944 had progressed only as far as the Gustav Line south of Rome. So the Allies staged a massive amphibious operation to force the defenders to split their forces or be surrounded, but quick success depended on a rapid break-out from the beachhead. Some 36,000 men landed to the enemy’s considerable surprise, but while the Allies consolidated, the Germans surrounded the area with equivalent forces and dug defensive positions. After heavy fighting and failed advances, in February the Allies were pushed back almost to the beachhead. It took more than 100,000 more reinforcements and five months of fighting to finally break out of Anzio.

After Anzio, the Germans occupied defensive positions known as the Winter Line, consisting of bunkers, barbed wire, minefields and ditches. The four successive Allied assaults on these positions became known as the Battle of Monte Cassino. The fight resembled a WW1 battle, with artillery bombardments preceding bloody infantry assaults on fixed positions. Success was bought at the cost of more than 50,000 casualties on the Allied side. Today, the battle is mainly remembered for the destruction of the abbey of Monte Cassino (which was sheltering civilians) by more than a hundred B-17 Flying Fortresses, when the Allies mistakenly believed the abbey to be a German artillery observation position.