Confoederatio cum principibus ecclesiasticis

The Confoederatio cum principibus ecclesiasticis ("Treaty with the princes of the church") was decreed on 26 April 1220 by Frederick II as a concession to the German bishops in return for their co-operation in the election of his son Henry as King.

It was an important source of law of the Holy Roman Empire, and was counted among its constitutional documents by the editors of the Monumenta Germaniae Historica.

In this law Frederick II relinquished a number of important Royal rights (Regalia) to the spiritual princes.

Among other things, the bishops received the rights to mint coins and levy tolls in the German part of the Holy Roman Empire and to build fortifications.

Moreover, they gained the right to hold courts in their lordships and to receive the assistance of the King or the Emperor in carrying out the sentences passed there.