Background and Causes of War – A Timeline

May 30 is Memorial Day. On this day, we honor and mourn the loss of US military personnel who have died while serving in the United States armed forces. Conflict stretches across time. It’s one of many consistencies throughout history. What changes is the reason for this conflict. In general, the 8 most common reasons for war include:

  1. Economic gain.
  2. Territorial gain.
  3. Religion.
  4. Nationalism.
  5. Revenge.
  6. Civil war.
  7. Revolutionary war.
  8. Defensive war.

Below is a list of some of the causes for key wars in United States’ history. Although there are many factors that lead to war, the list below highlights only the key ones.

1763 – Britain passes the Proclamation Act, which makes a border line along the Appalachian Mountains. Settlers are unable to move West beyond this line.

1767 – The colonists become increasingly angry after Britain passed many Acts that taxed them. They refuse to pay taxes when they do not have any representation in the government that taxed them.

March, 1770 – The Boston Massacre occurs when British soldiers shoot and kill 5 colonists.

April 19, 1775 – The American Revolutionary War begins.

1840 – The northern states oppose slavery.

1860 – The southern states secede when Abraham Lincoln is elected president.

April 12, 1861 – The American Civil War begins.

June 28, 1914 – Archduke Franz Ferdinand is assassinated with his wife in Sarajevo.

July 28, 1914 – World War 1 begins.

April 2, 1917 – The United States enters World War 1.

June 28, 1919 – Germany is forced to sign the Treaty of Versailles, ending World War 1.

Late 1920s – Worldwide economic depression.

1933 – Adolf Hitler becomes the leader of Germany.

1936 – Hitler orders German troops into France, Austria and Czechoslovakia.

September 1, 1939 – Germany invades Poland, which starts World War 2.

December 1941 – Japan attacks Pearl Harbor, Hawaii. The United States enters World War 2.

1945 – After the end of World War 2, the United States and Soviet Union fight to free Korea from Japanese rule.

September 2, 1945 – Ho Chi Minh declares Vietnam’s independence from France.

1949 – US and Soviet Troops leave North and South Korea.

June 25, 1950 – North Korea invades South Korea and the Korean War begins.

July 1950 – The United States enters the Korean War on behalf of South Korea.

July 1954 – The Geneva Accords are signed, splitting Vietnam in half. North Vietnam is ruled by Ho Chi Minh’s communist government. South Vietnam is ruled by emperor Bao Dai, and later Ngo Dinh Diem.

November 1963 – Ngo Dinh Diem and his brother, Ngo Dinh Nhu are murdered. Twelve different government successions follow between 1963 and 1965.

March 1965 – The United States enters the Vietnam War.

1980s – Kuwait loans billions of dollars to Iraq as aid during the Iran-Iraq War. When the war ended, Kuwait demanded repayment.

July 1990 – Saddam Hussein accuses Kuwait of stealing oil from Iraq.

August 2, 1990 – Saddam Hussein invades Kuwait.

January 16, 1991 – The Persian Gulf War begins.

1998 – President Clinton orders a series of air strikes against targets where it was believed weapons of mass destruction were being made in Iraq.

September 11, 2001 – The terrorist group al-Qaeda takes responsibility for the attack on the World Trade Centers in New York.

2002 – President Bush accuses Iraq of building weapons of mass destruction and supporting al-Qaeda.

March 19, 2003 – The Iraq War begins.

Click here for a free printable version of this timeline.

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