Hampshire tribes of northeastern Gaul - whether these two events are linked to the decline of hillforts is unknown. By the Roman conquest, the "oppidum" at Venta Belgarum, modern-day Winchester, was the "de facto" regional administrative centre; Winchester was, however, of secondary importance to the Roman-style town of Calleva Atrebatum, modern Silchester, built further north by a dominant Belgic polity known as the Atrebates in the 50s BCE. Julius Caesar invaded southeastern England briefly in 55 and again in 54 BCE, but he never reached Hampshire. Notable sites from this period include Hengistbury Head (now in Dorset), which was a major
Venta Belgarum east. Excavations of the cemetery were carried out by British archaeologist Julian Richards in 1998, and again in 2013, as part of the BBC television "Meet the Ancestors" series. From the mid-4th century, new development at Venta halted. Houses fell into disrepair and the drainage system collapsed. The population concentrated itself in the higher and drier areas of the town. The defences were however strengthened and the cemeteries remained in use, notably with burials of males wearing so-called military-style mercenary belts. Historian David Nash Ford identifies the community as the ("Fort Venta") listed by Nennius among the 28 cities of