Why did some people want to kill King James 1?

the group of catholics wanted to assassinate him because he was a catholic but Gu Fawkes was innocent because he was set up by king James' servant! Guy Fawkes was found underneath parliament with a lot of gunpowder but he was set up by the lords servant who was a criminal) but apparently had a new start! A weird letter was sent to the lord telling him that there was a plot to blow up parliament. The servant was in charge when the guards went to search parliament for gunpowder. He waited 10 days after the letter was delivered, it was said that he waited until he knew Guy was in the basement!