When was a territory eligible for statehood?

A territory was eligible to apply for statehood when the population reached 60,000. This system remained in place through the admittance of the last two states, Alaska and Hawaii.

on april 6, 1917, the u.s. joined its allies--britain, france, and russia--to fight in world war i. under the command of major general john j. pershing, more than 2 million u.s. soldiers fought on battlefields in france.