John Calvin (1509 – 1564) was a French Protestant reformer, pastor and theologian. His main work is The Institutes of the Christian Religion. In this work, one of his main points is predestination.
Predestination is the belief that before we were created, God picked all the men that would go to heaven. Martin Luther, the man who began the Protestant Reform, taught this. However, Calvin took predestination one step further and said that God also picked all men that were to go to hell. This was, and still is, a very strong and hard-to-take part of Protestantism.