Northern Catalonia, North Catalonia or French Catalonia is the formerly Catalan-speaking and cultural territory ceded to France by Spain through the signing of the Treaty of the Pyrenees in 1659 in exchange of France's effective renunciation on the formal protection that it had given to the recently founded Catalan Republic. The area corresponds roughly to the modern French département of the Pyrénées-Orientales which were historically part of Catalonia since the old County of Barcelona, and lasted during the times of the Crown of Aragon and the Principality of Catalonia until they were given to France by Spain.

The Pyrenees are a mountain range straddling the border of France and Spain. They extend nearly 500 km (310 mi) from their union with the Cantabrian Mountains to Cap de Creus on the Mediterranean coast, reaching a maximum altitude of 3,404 metres (11,168 ft) at the peak of Aneto.