Hitler invades Poland, starting WWII in Europe.
Roosevelt forms the Uranium Committee at the urging of Albert Einstein to begin work on an atomic bomb.
The Soviets invade Finland, but the Finns put up a much stronger defense than expected. After three months of fighting Finland cedes some border territories, and the Russians accept the terms on account of their immense loss of troops.
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Germans trap the British and French forces at Dunkirk. Almost miraculously, though, the troops are evacuated by the Royal Navy as well as thousands of British fishing boats. However, this event pushed the allies almost completely off the European continent.
Germany begins bombing England in preparation for a planned invasion. Over the course of the next few months, the tenacious British defense would cause the invasion to be put off indefinitely.
The Export Control Act is passed in the United States, limiting sale of arms and other materials, including scrap iron and gasoline, to Japan.
Japan signs the Tripartite agreement, forming an alliance with Germany and Italy.
American code breakers decipher the Japanese diplomatic code, called "Purple", allowing the United States to read Japanese messages. Over the next year this would allow America to discover that Japan planned to expand either to the southwest (Singapore), to the south (Phillipines), to the southeast (Pearl Harbor), or all three. The Japanese believed this code to be unbreakable through the entire war.
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To avoid interference from the Russians in the north, Japan signs a nonaggression pact with the Soviets.
A German U-Boat sinks the Robin Moor, an American ship.
Germany invades Russia with about 4 million soldiers. Germany achieves many tactical victories against the Russians in the next four months.
The German navy torpedoes the American destroyer USS Kearny, which managed to make it back to port.
Despite early success against the Russians, the German army stalls outside Moscow and is pushed back, trapped, and destroyed by a Russian counter offensive.
The Germans sink the USS Reuben James, killing 115 American sailors.
The Japanese Imperial Navy bombs Pearl Harbor in a devastating surprise attack.
3 days after Roosevelt's Dec. 8 speech in which he called Dec. 7 "a date which will live in infamy", congress almost unanimously declares war on Japan.
Hitler declares war on the United States, following the advice of his foreign minister, Joachim von Ribbentrop, who said, "A great power does not allow itself to be declared war upon - it declares war on others."
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26 nations at war with the Axis powers sign the Declaration of the United Nations based on the principles of the Atlantic Charter. In this agreement they promised not to make peace with any of the Axis powers and agree to defeat Germany before Japan and Italy.
Executive order 9066 marks the beginning of the relocation of Japanese-Americans living on the west coast. Approximately 150,000 Japanese-Americans would be relocated in all. The U.S. government eventually disbursed more than $1.6 billion in reparations to the survivors and their heirs.
Singapore, one of Britain's most powerful naval bases, is taken over by the Japanese.
After the three month battle of Bataan, the Japanese forcibly relocate 60,000 to 80,000 Filipino and American prisoners to Camp O'Donnell. By the end of April only about 7,000 of these prisoners would remain.
Lt. Doolittle launches sixteen B-25 bombers from the Hornet and bombs Tokyo in broad daylight. Although the attack does not destroy any military targets, it significantly improves American morale and causing some of the Japanese population to doubt their military leaders.
The United States Navy decisively defeats an attack by the Japanese Imperial Navy despite being outnumbered. Japan loses four modern carriers and more than 300 pilots, irreparably damaging her fleet. Japan will not attain another major victory after this point.
After much pressure from the Soviet Union, the United States and Britain open a second front by invading North Africa. By May 1943 the Mediterranean will have been secured for the Allies, marking the first major defeat for Germany.
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Roosevelt and Churchill meet in Casablanca to discuss war strategy. They agree to defeat Germany before Japan and to demand unconditional surrender from all Axis parties. They also agree that 80 percent of America's war production would go toward the European theater.
In April British Intelligence had staged an elaborate hoax, allowing a corpse with information that an invasion would take place in Greece to wash up on the Spanish coast. This caused the German army to move resources away from Sicily, the where the real invasion would take place, paving the way for the invasion of Italy three months later.
Mussolini resigns from power, giving the government of Italy back to Victor Emmanuel III.
Although Italy surrenders after the invasion, the Allies cannot move quickly due to German resistance and by D-Day they will have only moved 200 miles.
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The Allies launch an invasion by sea at Normandy, marking the beginning of the fall of Germany.
Several of Hitler's Generals attempt to assassinate him in Wolf's Lair. The assassination attempt fails and nearly all the culprits are executed.
The Allies bypass Paris to conserve fuel, but allow the Free French liberate the city.
The Germans rip a 45 mile hole in the Allied lines, but are quickly stopped by 11,000 trucks and 60,000 men a few days later.
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American troops land on Iwo Jima. Iconic flag raising. Only 200 of the 21,000 defenders surrender alive.
American troops land on Okinawa, an island 350 miles south of Japan. Hundreds of civilian families committed suicide rather than surrender to the Americans.
Germany surrenders unconditionally to the Allies.
The first atomic bomb is detonated at Trinity Island.
The Enola Gay drops the first atomic bomb in combat on Hiroshima, killing between 90,000 and 166,000.
The Bockscar drops the second atomic bomb in combat on Nagasaki, killing between 60,000 and 80,000.
The Japanese unconditionally surrenders to the Allies, ending World War II.
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