This surname comes from an old family (de Didilmissen) that lived near the modern towns of "Dielmissen" and "Bodenwerder" in modern Lower Saxony (Niedersachsen).
Towns along the Weser, from the confluence of Werra and Fulda to the mouth, include: Hann. Münden, Beverungen, Höxter, Holzminden, Bodenwerder, Hameln, Hessisch Oldendorf, Rinteln, Vlotho, Bad Oeynhausen, Porta Westfalica, Minden, Petershagen, Nienburg, Achim, Bremen, Brake, Nordenham, Bremerhaven.