John Calvin, or Jean Cauvin (1509-1564), French theologian. Calvin was born at Noyon in Picardy. The son of a cathedral notary, he was intended for the priesthood. He studied at Paris, then moved to Orleans to study law in 1526. It was there he first encountered humanism with its stress on classical studies and shortly after experienced a religious conversion that marked his break with the Roman Catholic Church. With religious violence in France, Calvin fled to Basel where he published his Institutes of the Christian Religion, then to Geneva where he had been invited to help reform the church. Calvin's writing had a huge influence on the Protestant church in Europe, although it varied in many respects from the existing Lutheran position. Calvin's writings formed the basis of Calvanist theology, later embodied in the Presbyterian and Reformed churches.