The spanish inquisition was originally established for the purpose of persecuting

heretics
jews
muslims
traitors

The answer is: heretics

Heretic is a term given to the people who are not willing to accept religious teachings. At that time, the Spanish empire made Catholicism as a national religion and enforce its citizens to follow the belief. If they refuse they could either jailed or executed.

At that time, atheists were not the only one that became the victim of Spanish Inquisition. Even though technically they believe in God, people with different religion such as Jews, Muslims, or Buddhist also became the target for execution.

an unexpected salary cut

confederacy: supported slavery, believed states should be able to nullify federal laws, supported low tariffs

union: everything else