GALLIA CISALPINA (Lat. Cis, on this side, i.e. of the Alps), in ancient geography, that portion of northern Italy north of Liguria and Umbria and south of the Alps, which was inhabited by various Celtic and other peoples, of whom the Celts were in continual hostility to Rome. In early times it was bounded on the S. by Liguria and the Aesis, in Caesar’s time by Liguria and the Rubicon. After the Second Punic War (203 B.C.) these tribes were severely punished by the Roman generals for the assistance they had rendered to Hannibal. Sulla divided the district into two parts; the region between the Aesis and the Rubicon was made directly subject to the government at Rome, while the northern portion was put under a distinct authority, probably similar to the usual transmarine commands (see Mommsen, Hist. of Rome, Eng. trans., bk. iv. c. 10).
For the early Celtic and other peoples and the later history of the district see Italy (ancient), and Rome: History, Ancient.