Martin Luther:He was a German theologian and key figure in the Protestant Reformation. Luther's Ninety-Five Theses, which criticized the sale of indulgences, sparked widespread debate and led to the formation of new Christian denominations.
John Calvin: A French theologian who played a significant role in shaping Protestantism. His teachings emphasized predestination and the idea that salvation is granted by God's grace alone.
Counter-Reformation:This term refers to the Catholic Church's response to the Protestant Reformation, aiming to address some of the criticisms raised by reformers and reaffirm its authority.