How did Asia got involved in World War 1?

What countries in Asia got involved and how? Any treaties signed?

the biggest factor i can think of is: britain controlled many places, such as hong kong and india (not sure about hong kiong at the time)

wars are very very complicated. but you have to remember one thing: when there's a war, everyone who can get pulled in does get pulled in.

for example, australia had a draft during WWI because it was still part of britain.

in the same way, othere places were pulled in due to protectorates, alliances, and enemies.

Almost everybody from China(whom Japan invaded before the war in Europe started to Russia who entered (as part of the victory treaty in Europe) after the first atomic bomb was dropped.