Treaty of Chambord

The Treaty of Chambord was an agreement signed on 15 January 1552 at the Château de Chambord between the Catholic King Henry II of France and three Protestant princes of the Holy Roman Empire led by Elector Maurice of Saxony. Based on the terms of the treaty, Maurice ceded the vicariate over the Three Bishoprics of Toul, Verdun, and Metz to France. In return, he was promised military and economic aid from Henry II in order to fight against the forces of Emperor Charles V of Habsburg.

After Emperor Charles V had defeated a number of revolting Protestant princes in the Schmalkaldic War, he in 1548 issued the geharnischt (sharply worded) Augsburg Interim in order to re-integrate the Lutheran movement into the established Catholic Church and to prevent the split of the Empire. To defend their autonomy, several Protestant Imperial States reacted with the 1551 Alliance of Torgau; first of all the Saxon elector Maurice of Wettin, who in the Schmalkaldic War had been a strong supporter of the emperor, but also William IV of Hesse-Kassel, the warlike Hohenzollern margrave Albert Alcibiades of Brandenburg-Kulmbach and his cousin the Prussian duke Albert.

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