History of Europe

Which factor helped shift American opinion away from neutrality during world war 1?

The sinking of the Lusitania: The sinking of the British passenger ship Lusitania by a German U-boat in May 1915 was a major turning point in American public opinion. Over 1,100 people, including 128 Americans, were killed in the attack. The sinking of the Lusitania caused widespread outrage in the United States and helped to solidify support for the Allied cause.