World War II ended six years and one day after Germany’s invasion of Poland on September 1, 1939, sparked the 20th century’s second global conflict. By the time it concluded on the deck of an American warship on September 2, 1945, World War II had claimed the lives of an estimated 60-80 million people, approximately 3 percent of the world’s population. The vast majority of those who died in history’s deadliest war were civilians, including 6 million Jews killed in Nazi concentration camps during the Holocaust.

Germany employed its “blitzkrieg” (“lightning war”) strategy to sweep across the Netherlands, Belgium and France in the war’s opening months and force more than 300,000 British and other Allied troops to evacuate continental Europe from Dunkirk. In June 1941, German dictator Adolf Hitler broke his nonaggression pact with the Soviet Union and launched Operation Barbarossa, which brought Nazi troops to the gates of Moscow.

By the time the United States entered World War II following the Japanese bombing of Pearl Harbor, German forces occupied much of Europe from the Black Sea to the English Channel. The Allies, however, turned the tide of the conflict, and the following major events brought World War II to an end.

1. The Battle of Stalingrad and Allied Invasions Shaped the End of WWII

After storming across Europe in the first three years of the war, overextended Axis forces were put on the defensive after the Soviet Red Army rebuffed them in the brutal Battle of Stalingrad, which lasted from August 1942 to February 1943. The fierce battle for the city named after Soviet dictator Joseph Stalin resulted in nearly two million casualties, including the deaths of tens of thousands of Stalingrad residents.

As Soviet troops began to advance on the Eastern Front, the Western Allies invaded Sicily and southern Italy, causing the fall of Italian dictator Benito Mussolini’s government in July 1943. The Allies then opened a Western Front with the amphibious D-Day invasion of Normandy on June 6, 1944. After gaining a foothold in northern France, Allied troops liberated Paris on August 25 followed by Brussels less than two weeks later.

2. The Battle of the Bulge Marks Germany's Last Stand

Germany found itself squeezed on both sides as Soviet troops advanced into Poland, Czechoslovakia, Hungary and Romania while the Western Allies continued to push eastward. Forced to fight a two-front war with dwindling resources, an increasingly desperate Hitler authorized a last-ditch offensive on the Western Front in hopes of splitting the Allied lines. The Nazis launched a surprise attack along an 80-mile, densely wooded stretch of the Ardennes Forest in Belgium and Luxembourg on December 16, 1944.

The German onslaught caused the Allied line to bulge, but it would not break during six weeks of fighting in subzero conditions that left soldiers suffering from hypothermia, frostbite and trench foot. American forces withstood the full might of what was left of Germany’s power but lost approximately 20,000 men in what was their deadliest single battle in World War II. What became known as the Battle of the Bulge would turn out to be Germany’s last gasp as the Soviet Red Army launched a winter offensive on the Eastern Front that would have them at the Oder River, less than 50 miles from the German capital of Berlin, by the spring.

3. The Liberation of Concentration Camps and Hitler's Suicide

After the firebombing of Dresden and other German cities that killed tens of thousands of civilians, the Western Allies crossed the Rhine River and moved eastward toward Berlin. As they closed in on the capital, Allied troops discovered the horror of the Holocaust as they liberated concentration camps such as Bergen-Belsen and Dachau. With both fronts collapsing and defeat inevitable, Hitler committed suicide in his bunker deep below the Reich Chancellery on April 30, 1945.

Hitler’s successor, Grand Admiral Karl Dönitz, started peace negotiations and on May 7 authorized General Alfred Jodl to sign an unconditional surrender of all German forces to take effect the following day. Stalin, however, refused to accept the surrender agreement inked at the headquarters of U.S. General Dwight D. Eisenhower in Reims, France, and forced the Germans to sign another one the following day in Soviet-occupied Berlin.

4. Atomic Bombing of Hiroshima and Nagasaki

Even after the Allied victory in Europe, World War II continued to rage in the Pacific Theater. American forces had made a slow, but steady push toward Japan after turning the course of the war with victory at the June 1942 Battle of the Midway. The Battles of Iwo Jima and Okinawa in the winter and spring of 1945 were among the bloodiest of the war, and the American military projected that as many as 1 million casualties would accompany any invasion of the Japanese mainland.

Weeks after the first successful test of the atomic bomb occurred in Alamogordo, New Mexico, on July 16, 1945, President Harry Truman, who had ascended to the presidency less than four months earlier after the death of Franklin D. Roosevelt, authorized its use against Japan in the hopes of bringing a swift end to the war. On August 6, 1945, the American B-29 bomber Enola Gay dropped an atomic bomb on the manufacturing city of Hiroshima, immediately killing an estimated 80,000 people. Tens of thousands later died of radiation exposure. When Japan failed to immediately surrender after the bombing of Hiroshima, the United States detonated an even more powerful atomic bomb on Nagasaki three days later that killed 35,000 instantly and another 50,000 in its aftermath.

5. The End of World War II: Soviets Declare War and Japan Surrenders

In addition to the bombings of Hiroshima and Nagasaki, Japan came under increasing pressure when the Soviet Union formally declared war on August 8 and invaded Japanese-occupied Manchuria in northeastern China. With his Imperial Council deadlocked, Japan’s Emperor Hirohito broke the tie and decided that his country must surrender. At noon on August 15 (Japanese time), the emperor announced Japan’s surrender in his first-ever radio broadcast.

On September 2, World War II ended when U.S. General Douglas MacArthur accepted Japan’s formal surrender aboard the U.S. battleship Missouri, anchored in Tokyo Bay along with a flotilla of more than 250 Allied warships.

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At the signing of the agreement that brought an end to 2,194 days of global war, MacArthur told the world in a radio broadcast, “Today the guns are silent. A great tragedy has ended. A great victory has been won.”