Reimer was born in 1770 to Heinrich Reimer and Agatha Epp (b. 1745) in the Vistula delta Mennonite settlement of Petershagen, Prussia, located about 35 km east of the city of Danzig (Gdańsk).
Minden Land in its narrower sense includes the towns and villages of Minden, Hille, Petershagen and the northern part of Porta Westfalica, as well as Lübbecke, Espelkamp, Preußisch Oldendorf, Rahden and Stemwede in Lübbecke Land.
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.