Bassum is a town in the district of Diepholz, Lower Saxony, Germany. It is situated approximately 35 km northeast of Diepholz, and 25 km south of Bremen. Wikipedia page  refers.
The Stadtarchiv Bassum serves the city and was founded in 1982 on the initiative of pastor Frithjof Bestmann, and moved to its current location in 1992.
More information on the German Wikipedia page