The name Vindobona derives from a Celtic language, suggesting that the region must have been inhabited before Roman times. The Romans created a military camp (occupied by Legio X Gemina) during the 1st century on the site of the city centre of present-day Vienna. The settlement was raised to the status of a municipium in 212. Even today, the streets of the First District show where the encampment placed its walls and moats. The Romans stayed until the 5th century.
Roman Vindobona was located in the outskirts of the empire and thus fell prey to the chaos of the Völkerwanderung. There are some indications that a catastrophic fire occurred around the beginning of the 5th century. However, the remains of the encampment were not deserted, and a small settlement remained. The streets and houses of early medieval Vienna followed the former Roman walls, which gives rise to the conclusion that parts of the fortification were still in place and used by the settlers. The first documented mention of the city during the Middle Ages dates to 881 when a battle apud Weniam was fought against the Hungarians. However, it is unclear whether this refers to the city or the River Wien. Early Vienna was centred around the Berghof.
Byzantine copper coins from the 6th century have been found several times in the area of today's city centre, indicating considerable trade activity. Graves from the 6th century were found during excavations next to the Berghof, in an area around Salvatorgasse. At that time, the Lombards controlled the area, with Slavs and Avars following later. The Salzburg Annals mention a battle against the Magyars at a location called Wenia in 881, which may be a reference to Vienna. Emperor Otto I defeated the Magyars in 955 in the Battle of Lechfeld. This allowed early Vienna to start to develop towards the Middle Ages.