It means you were sworn into the armed services.
He has joined (or been drafted) into a specific unit and placed on their muster role.
Gone To Texas
This means that the civil war was brutal .....
Do you mean the Spanish Civil War or the American Civil War?
If by Civil War you mean the War between the States in the US, then no. If you mean some other civil war, then maybe, you'll need to be more specific.
better question is which civil war.
Montana was not a State at the time of the Civil War.
The years immediately after the US Civil War were known as the ReconstructionReconstruction
No that was 1865, if you mean the American civil war.
You need to specify whether you mean the English Civil War or the American Civil War.
If you mean the American Civil War, they weren't expelled. There weren't very many in the US at that time, but there was no reason to throw them out.
Post means after, so post-Civil War means after the Civil War ended.