- Battle of Britain (July 1940 – October 1940): The Battle of Britain saw the British Royal Air Force (RAF) defeat the German air force, known as the Luftwaffe, effectively saving Britain from a proposed German amphibious invasion codenamed Operation Sea Lion. The primary German fighter plane was the Messerschmitt Bf 109, which engaged in numerous dogfights against British pilots flying Hurricane and Spitfire aircraft. Effective use of radar helped to repel German forces, forcing the Luftwaffe into nighttime raids against civilian targets, a campaign known as the Blitz.
- Battle of Stalingrad (August 1942 – February 1943): With about two million casualties, the Battle of Stalingrad is often cited as the bloodiest battle in history. The battle arose out of Germany’s summer campaign to capture vital oil supplies in the Caucasus Mountains, but Friedrich Paulus’s 6th Army became bogged down in intense street fighting in the city, allowing Soviet Marshal Georgy Zhukov to launch Operation Uranus, which encircled Paulus’s men by defeating the Italian, Hungarian, and Romanian forces guarding their flank. In the final days of the battle, Hitler promoted Paulus to field marshal, a not-so-subtle suggestion that Paulus should either fight to the death or commit suicide, as no German field marshal had ever been captured; Paulus surrendered anyway.
- Battle of El Alamein (October 1942 – November 1942): The Second Battle of El Alamein marked the turning point in the African campaign. Named for an Egyptian coastal town 65 miles west of Alexandria, it saw the British Eighth Army under Bernard Montgomery defeat the German Afrika Korps under Erwin Rommel, preventing the Nazis from capturing the Suez Canal and oil fields in the Middle East. Following the battle, Allied forces landed in Morocco and Algeria as part of Operation Torch, and by May 1943 all Axis forces in North Africa had surrendered.
- Battle of Kursk (July 1943 – August 1943): Fought in western Russia, the Battle of Kursk was the largest tank battle in history, with about 6,000 tanks engaged. Thanks to a complex spy network, the Soviet leadership was well-informed about German plans to launch Operation Citadel against the Kursk salient, and constructed massive defensive fortifications. After the German advance was stopped, a successful Soviet counterattack was launched. The German Army never again was able to mount a major attack on the Eastern Front.
- D-Day (Operation Overlord) (June 6, 1944): The largest amphibious assault in history, as Supreme Allied Commander Dwight Eisenhower’s forces attacked the German Atlantic Wall defenses on the beaches of Normandy, France. Due to his wife’s birthday, German Field Marshal Erwin Rommel was absent at the start the invasion, which saw American forces land at Utah and Omaha Beaches, British forces land at Gold and Sword Beaches, and Canadian forces land at Juno Beach. After the landings, Allied forces erected prefabricated artificial Mulberry harbors to aid in transporting goods to France.
- Battle of the Bulge (December 1944 – January 1945): The Battle of the Bulge resulted from Germany’s last major offensive operation on the Western Front. The German plan to sweep through the Ardennes Forest and capture the port city Antwerp, Belgium, benefited from Allied aircraft being grounded due to poor weather. During the battle, English-speaking German troops under Otto Skorzeny attempted to disguise themselves as Allied troops and infiltrate enemy lines. German forces also besieged the Belgian town Bastogne and requested its surrender, to which U.S. Army Brigadier General Anthony McAuliffe replied “Nuts!”; the siege was eventually lifted by forces commanded by George Patton.
Other notable battles in Europe included the Battle of France, the Siege of Leningrad, the Battle of Moscow, the Battle of Anzio, the Battle of Monte Cassino, Operation Market Garden, and the Battle of Berlin.
- Attack on Pearl Harbor (December 7, 1941): On what President Franklin Roosevelt declared would be “a date which will live in infamy,” Japanese carrier-based aircraft launched — without a formal declaration of war — a surprise attack on the American naval base at Pearl Harbor on the Hawaiian island Oahu. The attack sank four battleships, most notably the USS Arizona, but all of the U.S. Navy’s carriers were at sea and were unattacked. Shortly after the attack, Japan began invasions of Guam, Wake Island, the Philippines, and the British colony of Singapore. On December 8, with only Montana Representative Jeannette Rankin dissenting, the U.S. Congress declared war on Japan.
- Battle of the Coral Sea (May 1942): Resulting from a Japanese plan to capture Port Moresby, New Guinea, the Battle of the Coral Sea was fought entirely by carrier-based aircraft, making it the first major naval battle in history in which the two opposing fleets never directly fired upon (or even sighted) each other. The U.S. Navy’s carrier Lexington was sunk, and the Yorktown heavily damaged, while the Japanese navy lost the light carrier Shoho and saw its large carriers Shokaku and Zuikaku damaged. Ultimately, the invasion of Port Moresby was cancelled and the temporary loss of two Japanese carriers gave the U.S. an edge at the subsequent Battle of Midway.
- Battle of Midway (June 1942): Universally considered the turning point in the Pacific Theater, the Battle of Midway saw the Japanese lose four aircraft carriers, a blow from which they never fully recovered. Japanese Admiral Isoroku Yamamoto planned to lure the U.S. fleet into a trap, but the Americans had broken the Japanese code, allowing them to pull off a stunning victory, with dive bombers from the Enterprise sinking the carriers Kaga, Akagi, and Hiryu, while those from the hastily-repaired Yorktown sank the carrier Soryu.
- Battle of Leyte Gulf (October 1944): By some measures the largest naval battle in history, the Battle of Leyte Gulf resulted from the Japanese Sho-Go plan to halt the American reconquest of the Philippines. The plan nearly worked when American Admiral William “Bull” Halsey was baited into moving all of his battleships and large carriers away from the landing site, but an American force of small escort carriers and destroyers held off a Japanese task force that included four battleships. Another Japanese force tried to pass through the Surigao Strait, but — in the last-ever combat between opposing battleships — the American Seventh Fleet crossed their ‘T’ and annihilated the force.
- Battle of Iwo Jima (February 1945 – March 1945): The Allies sought to capture Iwo Jima, a small island midway between the Mariana Islands and the Japanese home islands, to provide an airbase for the eventual invasion of Japan. Under the leadership of General Tadamichi Kuribayashi, the island’s defenders built a complex network of underground tunnels and well-camouflaged artillery pieces that enabled them to hold out for a month against vastly superior forces. The battle is best known for Joe Rosenthal’s photograph showing six American servicemen raising a flag atop Mount Suribachi.
- Battle of Okinawa (April 1945 – June 1945): The largest amphibious assault of the Pacific Theater, the Battle of Okinawa featured massive casualties among both combatants and civilians. The Japanese launched over 1,500 kamikaze attacks against the U.S. fleet, and even sent the massive battleship Yamato on a suicide mission; it was sunk by aircraft before reaching Okinawa. On the American side, both war correspondent Ernie Pyle and Lieutenant General Simon Bolivar Buckner Jr., the commander-in-chief of the ground forces, were killed. Somewhat uniquely, the battle also saw large numbers of Japanese troops surrender, although many were native Okinawans forced into fighting.
Other notable clashes and incidents in the Pacific included the Bataan Death March, the Battle of Guadalcanal during the Solomon Islands campaign, the Battle of the Philippine Sea, and the atomic bombings of Hiroshima and Nagasaki.