A long-time fight between Catholic France and Protestant England for Scotland began again because of the Reformation. As the argument grew more heated, sometimes France had power, sometimes England. Knox spent many months as a galley slave; he also spent time in exile because of his Protestant beliefs. During a return visit to his native land, Knox's preaching helped the Protestant movement. Several Protestant noblemen came together and made a group called the Lords of the Congregation. When the group had more power, they invited Knox back to Scotland to stay.