Pearl Harbor Timeline
Timeline Description: The attack on Pearl Harbor in 1941 was a day in American history that should always be remembered. It changed the course of WWII and history. This is a timeline of what led to that day and beyond.

Date Event
1937 Japan invades China

Japanese troops invaded China from the north.
1939 World War II begins

WWII began in 1939, involving several countries like England, Germany, and Japan. America didn't join in the war when it began.
1940 America boycotts Japan

American made new trade sanctions that limited how Japan could trade their goods. This was because of Japan's actions in the war.
January 1941 Japan begins preparing an attack

America was not active in WWII yet. Because of the trade bans, Japan decided to either bully Americans into lifting the bans, or bring America into the war.
January 1941 Americans didn't believe it

An American intercepted the Japanese messages about an attack on Pearl Harbor. He told his superiors, but no one believed him.
July 1941 Japan continues their preparations

Japanese troops prepared for the attack throughout the summer months.
September 1941 More messages are intercepted

American intelligence intercepted more Japanese messages about the attack on Pearl Harbor. The messages were asking about the location of the American military ships, but still no one believed it would happen and they didn't tell the Hawaii commanders.
November 1941 Japanese submarines leave Japan

Japan launched the first steps of their plan in sending out submarines to scout the waters around Pearl Harbor in Hawaii. Later that month they sent out their war ships.
November 1941 Americans finally believe it

The commanders in Hawaii were finally told about the messages of attack from the Japanese. They had little time to prepare.
December 7, 1941 The attacks begin

The first attacks on Pearl Harbor began early on Sunday morning. Waves of planes flew over the harbor, bombing everything in sight for over two hours.
December 8, 1941 America enters the war

Just as the Japanese wanted, America declared war on Japan. They were now fighting in WWII.
December 11, 1941 More enemies are declared

After America declared war on Japan, Germany and Italy declare war on the United States.
December 16, 1941 Hawaii commanders are relieved of their duties

The generals in charge of the Pearl Harbor troops were blamed for letting the attacks happen, and they were released from their positions. However, they were cleared from the blame years later when people realized no one had given them the warnings in time.
1945 The atomic bombs were tested (Early 1945)

The United States slowly developed atomic bombs during the war. In 1945 they tested them and knew they were ready for use.
August 1945 The US uses their atomic bombs

The American troops dropped two atomic bombs in Japan. Their successful drops ended WWII.






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