The earliest archaeological signs of permanent habitation in the Paris area date from around 4200 BC.The Parisii, a sub-tribe of the Celtic Senones, known as boatsmen and traders[citation needed], inhabited the area near the river Seine from around 250 BC[citation needed]. The Romans conquered the Paris basin in 52 BC, with a permanent settlement by the end of the same century on the Left Bank Sainte Geneviève Hill and the Île de la Cité island. The Gallo-Roman town was originally called Lutetia, but later Gallicised to Lutèce. It expanded greatly over the following centuries, becoming a prosperous city with a forum, palaces, baths, temples, theatres and an amphitheatre. The collapse of the Roman empire and the third-century Germanic invasions sent the city into a period of decline. By 400 AD Lutèce, by then largely abandoned by its inhabitants, was little more than a garrison town entrenched into the hastily fortified central island. The city reclaimed its original appellation of "Paris" towards the end of the Roman occupation.
