Both Lutheranism and Calvinism represent the success of their leaders in addressing issues within the Catholic Church during the 16th century. The two leaders were also responsible for the conflicts that spread across Europe after their ideas took hold. Martin Luther established his leadership primarily in northern Germany (Hunt 440), while John Calvin began his reforms in Geneva. From that point on, the peoples of Western Europe began to argue about which beliefs of religious leaders should be followed in their region. The expression of new ideas, championed during the Renaissance, allowed Luther and Calvin to challenge one of the most central and powerful aspects of life: the Church, which later provoked great conflicts throughout Europe as a church