Reichsfürst
The Coup of Kaiserswerth () in 1062 was a hitherto unprecedented action of several secular and ecclesiastical Princes of the Holy Roman Empire under the leadership of Archbishop Anno II of Cologne against Empress Agnes, ruling on behalf of her under-age son, King Henry IV, and against her chosen sub-regent, Bishop Henry II of Augsburg. By kidnapping the young king and enforcing the handover of the Imperial Regalia, the group gained control of the reins of power in the Empire.