Upper Brittany (French: Haute-Bretagne; Breton: Breizh-Uhel; Gallo: Haùtt-Bertaèyn) is the eastern part of Brittany, which is predominantly of a Romance culture and is associated with the Gallo language. The name is in counterpoint to Lower Brittany, the western part of the ancient province and present-day region, where the Breton language has traditionally been spoken. However, there is no certainty as to exactly where the line between 'Upper' and 'Lower' Brittany falls.
In many regards, Upper Brittany is dominated by the industrial and cathedral city of Rennes, seat of the University of Rennes 1 and the University of Rennes 2.
The principal distinction between the two parts of Brittany is that Lower Brittany is the historic realm of the Breton language, while Upper Brittany is that of Gallo, closely related to French. The isolation of Brittany from the mainstream of French society was always less acute in Upper than in Lower Brittany, largely thanks to the languages they spoke.
Together with other factors, this has led to other differences throughout history. The Revolt of the Papier Timbré of 1675 was more ferocious in Lower Brittany than in Upper, but the Chouannerie, a royalist uprising in the west of France against the French Revolution, the Republic, and the First Empire, enjoyed more support in Upper Brittany than in Lower. Upper Brittany accounted for some sixty per cent of the province's emigrants to French Canada, with especially high rates of emigration from Nantes and Ille-et-Vilaine, despite having a smaller population than Lower Brittany until the middle of the 20th century.