Question

What countries were in world war one, and when did they join?

Answer 1

I know the U.S and Britain was in WWI

Step-by-step explanation:

Answer 2

The war pitted the Central Powers (mainly Germany, Austria-Hungary, and Turkey) against the Allies (mainly France, Great Britain, Russia, Italy, Japan, and, from 1917, the United States). Read more about the Allied powers.