An Etymological Dictionary of the German Language/Annotated/herrschen
herrschen, verb, from Middle High German hersen, hêrsen, Old High German hêrisôn, ‘to rule, reign,’ but also hêrrisôn even in Old High German, from its association with hêrro, ‘lord’ (for Modern High German sch after r from an older s, compare Hirsch, Kirsche). The origin of the meaning ‘to rule’ cannot be explained from the posit. hehr, Old High German hêr, ‘august, exalted, venerable, glad,’ but from the originally comparative hêrro, ‘lord.’ Thus Old High German hêrisôn, ‘to be lord and master, dominari,’ is related to hêrro, hêriro, ‘lord,’ as Gothic *hairiza (comparative) is to *hairisôn, verb.