The Three Bishoprics ( ) constituted a government of the Kingdom of France consisting of the dioceses of Metz, Verdun, and Toul within the Lorraine region. The three dioceses had been Prince-bishoprics of the Holy Roman Empire until they were seized by King Henry II of France between April and June 1552. At the end of the Thirty Years' War, they were officially ceded to France by the 1648 Peace of Westphalia. History In the course of the rebellion against the Habsburg emperor Charles V, several Protestant Imperial princes met at Lochau Castle near Torgau in May 1551. Here the receiving Wettin elector Maurice of Saxony forged an alliance with Duke John Albert I of Mecklenburg, Prince William IV of Hesse, whose father Landgrave Philip I was jailed by the emperor, the Hohenzollern margrave Albert Alcibiades of Brandenburg-Kulmbach and his cousin Duke Albert of Prussia. Dissatisfied with the Interim decreed by Charles V at the 1548 Diet of Augsburg, the insurgents were full of resolution to defend Protestantism and–not least–their autonomy against the Imperial central authority. They agreed to establish contacts with the Catholic French king Henry II, disregarding his oppression of the Protestant Huguenots. In autumn Henry declared war against Charles V and prepared to march against the Empire up to the Rhine River. On 15 January 1552, he signed the Treaty of Chambord with Maurice of Saxony and his Protestant allies, whereby the French conquests were legitimised ahead of time. The princes acknowledged the king's lordship as "Vicar of the Empire" over the Imperial cities of Metz, Toul and Verdun, as well as Cambrai "and other towns of the Empire that do not speak German". The insurgents in turn received subsidies and military assistance from the French, their troops moved into the Habsburg hereditary lands and laid siege to the emperor at Innsbruck, while his brother Ferdinand I entered into negotiations that led to the revocation of the Augsburg Interim by the 1552 Peace of Passau. Backed by Duke Francis of Guise and his brother Cardinal Charles of Lorraine, King Henry II of France upon his agreement with the Protestant princes had started his Voyage d’Allemagne "for the sake of German liberties". On Palm Sunday 1552 French troops under the command of Anne de Montmorency in a surprise attack moved into the walls of Metz, followed by the occupation of Toul on 13 April. Henry then turned against