This is when Trench Warfare started.
It restricted free speech and arrested opponents of war. Also, anti war mail was prohibited and seized.
Russia tries to become a communist power and fight the Czars who are loyal to Russia's emperor. The allied powers gave supplies to the Czar forces.
All men ages 21 to 30 had to join the U.S. military.
A secret message was decoded and it said that the germans would help the mexicans take back all the land they lost in the mexican american war. If they helped the germans.
800,000 americans died
The U.S.A. was worried that if they went in to the league of nations because they might get sucked in to wars they don't want to fight.