(All of the above) is the answer
What could cause you to lose your citizenship of a certain country would be if you decided to betray your country for some reason in some way. This could be done in multiple fashions, one being if you're in the army and you give out a top military secret. This cold make you lose citizenship.
Because they thought the confederacy was going to attack their new territory
After the end of the Civil war, the Republican party was left unchallenged in its authority over the country. It then started the process of Reconstruction of the South. This was faced by vehement opposition from the majority in the South that had supported the Confederate course. Those that supported these reforms were those that had been marginalized in the slavery system in the South. Others that supported the reforms projected to benefit from economic opportunities created by carpetbaggers looking to assert their authority in the south... :)
Everything dies?( big chance im wrong )
