The Kingdom of Brittany emerges from the combination of the three earlier kingdoms of Armorica: Vannetais, Domnonee and Broerec.

It is one of the six predecessors to what are now known as the six Celtic nations.

The question of whether the kingdom was truly independent figures prominently in the history of its successor state, the sovereign Duchy of Brittany.

The Kingdom of Brittany preceded the Duchy which remained an independent sovereign state until its merger into the Kingdom of France in the 1500s.