World War I is the first war to use chemical weapons such as poison gas.
World War I is also known as a war to end all wars because of an effort to create an international organization to prevent conflict in the future.
During World War II, the United States launched a secret project called the Manhattan project to develop atomic bombs.
Adolf Hitler, Nazi leader, has a younger sister named Paula Hitler who survived the war and died in 1960.
World War II created many discoveries and innovations, including modern computers, rockets, jets, and radar.
Women play an important role in war, both as a member of the military and in factory work to support war efforts.
Japan launched a surprise attack on the American Navy Base in Pearl Harbor, Hawaii on December 7, 1941, which caused the United States to join in World War II.
Winston Churchill, British Prime Minister during World War II, known as his inspiring and motivational words, as we will fight on the beach, we will fight on the airport, we will fight in the fields and on the streets.
During the Vietnam War, the United States used chemical weapons such as orange agents to kill plants and forests used by North Vietnam troops.
Cold War is a political and military conflict between the United States and the Soviet Union which took place from the end of World War II to 1991.
