Treaty of Chambord

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.

Once the armistice with the Protestant princes was declared, Charles V during the Italian War of 1551–59 made several attempts to forcibly regain the overlordship over the Three Bishoprics, the disposal of which was his Imperial privilege.

The Treaty of Chambord was a typical international political example for an agreement at the expense of other parties ("ius quaesitum tertio", in English a "third-party beneficiary contract", in French “promesse de porte-fort”).

France used the convention as a pretence to militarily occupy the Three Bishoprics, to subsequently remove them out of the collective of the Holy Roman Empire and to incorporate them into its own territory.