Tarquinii (tärkwĬn´ēī), ancient city of Etruria, central Italy, NW of Rome. The head of the Etruscan League, it was defeated in wars with Rome in the 4th cent. BC In the 3d cent. BC it lost its independence. Tarquinii continued to exist far into the Christian era and was sacked by the Arabs. After the 9th cent. AD it was superseded by nearby Corneto, which is now called Tarquinia and has a museum with Etruscan antiquities. Much knowledge of Etruscan life has been gained from paintings on the walls of tombs in the necropolis of Tarquinii.