town and episcopal see, Piemonte ( Piedmont) region, northwestern Italy, on the Dora Baltea River, north of Turin. The importance of its gold mines led the Romans to seize the district from the Salassi in 143 BC. Ivrea was a Lombard duchy and, from the 9th century, a marquessate, and two of its rulers, Berengar II (950) and Arduin (1002), became kings of Italy. It passed to Monferrato in 1266 and to the House of Savoy in 1313. Served by rail and road, Ivrea manufactures office equipment (it is the headquarters of Olivetti) and textiles. Tourism is important, and the town's annual historical carnival in February is well known. Pop. (2006 est.) mun., 24,188.