President Woodrow Wilson confirmed that the U.S will not take sides on the war that was going on, WWl.
On June 28, 1914, Archduke Franz Ferdinand and his wife were assassinated in Sarajevo.
The Lusitania was torpedoed by Germany. About 1200 passengers died.
The Sussex Pledge was formed to save more innocent people, and to warn a ship before torpedoing it, but it doesn't last long because later on, Germany ignored is and announced that it would sink all ships armed or unarmed.
Germany pledges its U-boats to warn a ship before firing a torpedo
The British intercepted a secret telegram sent from Germany to Mexico, saying that Germany wanted Mexico to invade the U.S if the U.S joined the war in Europe. This angered Wilson and the Americans.
After the Germans sunk 4 more U.S ships, Woodrow Wilson has made the decision to ask Congress to declare war on Germany!