The Marburg Colloquy was a meeting at Marburg Castle, Marburg, Hesse, Germany which attempted to solve a dispute between Martin Luther and Huldrych Zwingli over the Real Presence of Christ in the Lord's Supper. It took place between 1 October and 4 October 1529. The leading Protestant reformers of the time attended at the behest of Philipp I of Hessen. Philipp's primary motivation for this conference was political; he wished to unite the Protestant states in political alliance, and to this end, religious harmony was an important constituent.