hmmmmmmmmmmmmmmmm

can we get it to start at 1900 and end 1950 i know that's a tall order just make for a nice long game

There is a transition, with either the second treaty of Frankfurt (CP victory) or the historical treaty of Versailles (Entente victory) that triggers if a side gains enough of an upper hand. You can refuse it, though, and go on until you just beat everything - locking out the interbellum Focus trees in the process.