 Rudolph II convoked the Imperial Diet to Regensburg and appointed Ferdinand as his deputy in November 1607.At the opening session of the Diet on 12 January 1608, Ferdinand demanded funds from the Imperial Estates on the Emperor's behalf to finance 24,000 troops.The delegates of the Protestant princes stated that they would vote for the tax only if the Catholic Estates accepted their interpretation of the Religious Peace of Augsburg, especially their right to retain the lands they had confiscated from Catholic clerics in their realms.