his nephew Bellovesus into northern Italy at the head of a party drawn from various Gaulish tribes; Bellovesus allegedly founded the settlement in the times of the Roman monarchy, during the reign of Tarquinius Priscus. Tarquin is traditionally recorded as reigning from 616 to 579 BC, according to ancient Roman historian Titus Livy. During the Roman Republic, the Romans, led by consul Gnaeus Cornelius Scipio Calvus, fought the Insubres and captured the settlement in 222 BC. The chief of the Insubres then submitted to Rome, giving the Romans control of the settlement. The Romans eventually conquered the entirety of the region, calling the new province "Cisalpine Gaul" () – "Gaul this side of the Alps" – and may have given the city its Latinized name of Mediolanum: in Gaulish *medio- meant "middle, centre" and the name element -lanon is the Celtic equivalent of Latin -planum "plain", thus *Mediolanon (Latinized as Mediolānum) meant "(settlement) in the midst of the plain". In 286, the Roman Emperor Diocletian moved the capital of the Western Roman Empire from Rome to Mediolanum. Diocletian himself chose to reside at Nicomedia in the Eastern Empire, leaving his colleague Maximian at Milan. Maximian built several gigantic monuments: the large circus (470 × 85 metres), the thermae or "Baths of Hercules", a large complex of imperial palaces and other services and buildings of which few visible traces remain. Maximian increased the city area to 375 acres by surrounding it with a new, larger stone wall (about 4.5 km long) with many 24-sided towers. The monumental area had twin towers; the one included later in the construction of the convent of San Maurizio Maggiore remains 16.6 m high. The Emperor Constantine issued the Edict of Milan from Mediolanum in 313 AD, granting tolerance to all religions within the Empire, thus paving the way for Christianity to become the dominant religion of Roman Europe. Constantine was in Mediolanum to celebrate the wedding of his sister to the Eastern Emperor, Licinius. In 402, the Visigoths besieged the city and the Emperor Honorius moved the Imperial residence to Ravenna. In 452 Attila in his turn besieged Mediolanum, but the real break with the city's Imperial past came in 539, during the Gothic War, when Uraia (a nephew of Witiges, formerly King of the Italian Ostrogoths) laid Mediolanum to waste with great loss of life. The Lombards took Ticinum as their capital in 572