The Reformation and Counter-Reformation
Provoked largely because of corruption and abuses in the Catholic Church, the Protestant Reformation arose to correct them while setting a new course on many matters of doctrine, such as justification by grace through faith alone and using the Bible as the only ultimate source of religious authority.
Martin *Luther (1483-1546): German monk, created controversy by his 95 theses against selling indulgences. Eventually ends up leading a movement that sets up a separate church, engages in major doctrinal changes.
John *Calvin (1509-1564): French lawyer, founded what eventually became a separate Protestant movement, the Presbyterian and Reformed churches. Argued for predestination in Institutes of the Christian Religion; Calvinism remains a major theological system in Protestantism.
*Counter-Reformation: The Catholic Church organizes new monastic orders like the Jesuits of Ignatius Loyola, takes back areas earlier lost to Protestantism, responds doctrinally at the Council of Trent (three sessions between 1545 and 1563) by affirming traditional doctrines. The Papacy is reformed morally and bureaucratically.