The five alpine cantons perceived the Reformation as a threat early on; already in 1524 they formed the "League of the Five Cantons" ("Bund der fünf Orte") to combat the spreading of the new faith. Both sides tried to strengthen their positions by concluding defensive alliances with third parties: the Protestant cantons formed a city alliance, including the Protestant cities of Konstanz and Strasbourg ("Christliches Burgrecht"), translated variously as Cristian Civic Union, Christian Co-burghery, Christian Confederation and Christian Federation (in Latin Zwingli called it Civitas Christiana or Christian State); the Catholic ones entered a pact with Ferdinand of Austria.