ANCUS MARCIUS (64o-616 B.c.), fourth legendary king of Rome. Like Numa, his reputed grandfather, he was a friend of peace and religion, but was obliged to make war to defend his territories. He conquered the Latins, and some of them whom he settled on the Aventine formed the origin of the Plebeians. He fortified the Janiculum, threw a wooden bridge across the Tiber, founded the port of Ostia, established salt-works and built a prison.
See Livy i. 32, 33 ; Dion Halic. iii. 36-45 ; Cicero, De Republica, ii. 18.