The French King, Louis XIV, revoked the laws that granted religious toleration to the Calvinists - also known as the the Huguenots - the Edict of Nantes, in 1685. This sparked a debate throughout Europe about the benefits and costs of a tolerant religious policy. John Locke wrote a series of “letters on toleration” and he was joined by the German jurist Samuel Pufendorf. The wars and revolutions in England from the 1640s to 1689 were concerned with questions of the religious persecution and toleration of Protestants and Catholics. William Penn was active in the 1670s and 1680s in arguing for religious liberty.