Officer belt buckle

[Skywise]

Sorry for the simplicity here, but what is the difference between the Indian war Officer belt buckle and a civil war officer belt buckle?

[CAC1901]

If you mean the eagle plate type - it depends. For about two decades after the war they were essentially the same, variances were based on who was manufacturing it. Over more decades the keeper or tongue catch grew wider, the wreath was often cast rather than applied, and the belt loop moved to the rear of the plate.  The variances in these plates could make a collection unto itself.