Anselm of Canterbury was an Italian Benedictine monk, philosopher, and theologian who lived from 1033 to 1109. He became the Archbishop of Canterbury and is best known for his works on the existence of God and the nature of faith. Anselm is often regarded as the father of scholasticism, a method of critical thought that dominated medieval universities. His most famous argument for the existence of God is known as the ontological argument, which posits that God, being the greatest conceivable being, must exist in reality because existence is a necessary attribute of greatness. Anselm's writings significantly influenced later theologians, including Thomas Aquinas and Martin Luther.