Until the Protestant Reformation, the Catholic faith of the kings and queens of Europe was an assumption, not a debate. As the fragment grenade of the reformation exploded across Europe, however, what was once assumed was now questioned. Many lesser nobles across Europe found the Reformed religions appealing and converted to Lutheranism and Calvinism, thereby destabilized the political order of Europe and often causing both political and social turmoil. These issues came to a point only in the French Wars of Religion, however, when a Calvinist prince became heir apparent to the throne of France.