The Revolutions of 1848 delayed Waitz in taking up his new chair. When the German party in Schleswig and the duchy of Holstein rose against the Danish government during the First Schleswig War, Waitz placed himself at the service of the provisional government. He was sent to Berlin to represent the interests of the duchies there, and during his absence he was elected by Kiel as a delegate to the Frankfurt Parliament. He was supported German unification; and when King Frederick William IV of Prussia declined the imperial crown Waitz withdrew from the assembly in disappointment, and left public life.