An Etymological Dictionary of the German Language/Annotated/er

by Friedrich Kluge

er, pronoun, ‘he, it,’ from Middle High German and Old High German ër, corresponding to the equivalent Gothic is, from a pronominal stem of the third person i-; compare Latin i-s (Latin id, Gothic ita, Old High German and Middle High German ëȥ, Modern High German es). Akin to the Sanscrit pronominal stem i-.