John Wilkes Booth was the assassin of beloved President and anti-slavery liberal Abraham Lincoln. He was an angry copperhead aka "peace democrat" (when that meant "pro slavery", of course). Booth was also an actor who sometimes found it difficult to tell the difference between stage drama and real life. At that time the Republicans were far more anti-slavery and liberal than the democrats and many Southern Democrats were KKK members.

Booth supported the Confederacy in the American Civil War and hoped killing Abraham Lincoln would prevent freed slaves getting the vote, because in the mind of a conservative, nothing is worse than giving minorities civil rights. This is why we have/need (depending on where you live) gun control. Just look what happens when you "give a Conservative a gun."