The source of the "contagion", as court pamphleteers put it, was ever Geneva, where the former Frenchman John Calvin achieved undisputed religious supremacy in 1555, the very year that the French Reformed Church organized itself at a synod under the king's nose, as it were, in Paris. At the Peace of Augsburg signed that same year in Germany, the essential concept was cuius regio eius religio, "Whose region, his religion". In other words, the religion of the king or other ruler would be the religion of the people. The petty princes of Germany were enabled to dictate the religion of their subjects, and it came to be sensed as a mark of weakness that the King of France could not do so: "One King, One Faith" would become the rallying cry of the ultra-Catholic party of the Guise faction.