Brittany's earliest known neolithic tribes left a legacy of menhirs and dolmens clustered across the region that continue to baffle historians. Celts arrived in the 6th century BC, naming their new homeland Armor ('the land beside the sea') and ultimately the region was conquered by Julius Caesar in 56 BC. Following the withdrawal of the Romans in the 5th century AD, another influx of Celts – driven from what is now Britain and Ireland by the Anglo-Saxon invasions – settled in Brittany, bringing Christianity with them.

In the 9th century, Brittany's national hero Nominoë (also spelled Nomenoë) revolted against French rule. Wedged between two more-powerful kingdoms, the duchy of Brittany was continually contested by France and England until a series of strategic royal weddings finally saw the region become part of France in 1532.

However, Brittany has retained a separate regional identity. A drive for cultural and linguistic renewal is afoot, and a consciousness exists of Brittany's place within a wider Celtic culture embracing Ireland, Wales, Scotland, Cornwall and Galicia in Spain.