In 1145 Ampass is mentioned for the first time in the documents as "Ambanes", a name derived from the Celtic meaning "between two rivers", at that time was under the jurisdiction of the Court of Sonnenburg.
1145. aastal on Ampassi esmakordselt dokumentides mainitud kui "Ambanes", nimi tähendas keldi keeles "kahe jõe vahel", oli sel ajal Sonnenburgi kohtu jurisdiktsiooni all.