My last name is Keller - German: from Middle High German kellaere ‘cellarman’, ‘cellar master’ (Latin cellarius, denoting the keeper of the cella ‘store chamber’, ‘pantry’). Hence an occupational name for the overseer of the stores, accounts, or household in general in, for example, a monastery or castle. Kellers were important as trusted stewards in a great household, and in some cases were promoted to ministerial rank.