Old English help (m.), helpe (f.) "assistance, succor;" see help (v.). Most Germanic languages also have the noun form, cf. Old Norse hjalp, Swedish hjälp, Old Frisian helpe, Dutch hulp, Old High German helfa, German Hilfe. Use of help as euphemism for "servant" is American English, 1640s, tied up in notions of class and race.
Though help also meant "assistant, helper, supporter" in Middle English (c.1200).