The Decapolis (Greek: "Ten Cities") was a region including 10 originally independent Greek city states, all of which lay east of the Jordan river except for Scythopolis [ancient Beth Shean]. Each city was the center of its own administrative district. Several were brought under Judean control by Aristobulus I and Alexander Jannai but were never Judaized. Pompey restored their nominal autonomy under the protection of the Roman governor of Syria. Augustus placed Gadara and Hippos under Herod. The synoptic gospels report several trips by Jesus into this largely non-Jewish region, but with imprecise geography. During the Jewish revolt [66-70 CE], Jewish Christians reportedly migrated to Pella.
Source: Into His Own