A passenger ship bombed by Germany

German submarines or "untersee boats"

a situation in which neither side can win a victory

An increase in the importance of a large, powerful military of a country

A group of nations (Great Britain, France, Russia, and later the United States) that allied to fight the Central Powers in WWI

The coalition of nation in WWI that included Germany, Austria-Hungary, and the Ottoman Empire

To prepare for war.

Payment for war damages made by the loser of a war.

A coalition of governments designed to find peaceful solutions to disagreements, proposed by Woodrow Wilson.

The treaty that ended WWI, but was never ratified by the United States.

A truce or cease-fire agreement between warring nations - an agreement to stop fighting

A new kind of warfare in WWI that involved troops digging and fighting from deep trenches.

Archduke of Austria-Hungary

The US military forces sent to Europe during WWI and led by General John J. Pershing.

People who believe in communism, or the political system in which all resources are shared equally.

Loans to the government that aided its ability to prepare for WWI.

A government agency organized to help settle disputes between workers and employers in war industries.

A 1917 law that allowed the president to draft soldiers in times of war.

US Senator who opposed the Treaty of Versailles. He declared: "No peace that satisfied Germany in any degree can ever satisfy us."