District in east central France, centred on the upper Marne but extending to the upper Meuse.
It was a County until the early 11th century (the name is said to come from an early Count), after which it broke up. In the south, the Bishop of Langres established quite a strong ecclesiastical principality for a while, but then the Dukes of Burgundy gained much influence there until 1179, when King Louis VII took Langres under royal protection.
Southern Bassigny later became part of Champagne after the Kings acquired that province. The northwestern part of Bassigny around Chaumont had for long belonged to Champagne, whilst the district around Bourmont, on the Meuse, to the east of Chaumont, formed a detached part of the County, later Duchy, of Bar. Most of Bassigny is now in the Department of the Haute-Marne.