Of Old Norse origin, from ei ‘ever, always’ (or einn ‘one, alone’) + ríkr ‘ruler’ (see Eirik). It was introduced into Britain by Scandinavian settlers before the Norman Conquest. As a modern given name, it was revived in the mid 19th century and has remained in use since.
Italian: from the personal name Saccomanno, originally a status name for someone who was in charge of transporting an army's baggage and supplies, or the personal servant of a knight on campaign, a loanword from medieval German (see Sackmann). Later it came to denote a marauder or plunderer.