The Celtic nations are a cultural area and collection of geographical regions in Northwestern Europe where the Celtic languages and cultural traits have survived. The term nation is used in its original sense to mean a people who share a common identity and culture and are identified with a traditional territory.. The six regions widely considered Celtic nations are Brittany (Breizh), …

The Celtic Sea is the area of the Atlantic Ocean off the south coast of Ireland bounded to the east by Saint George's Channel; other limits include the Bristol Channel, the English Channel, and the Bay of Biscay, as well as adjacent portions of Wales, Cornwall, and Brittany.The southern and western boundaries are delimited by the continental shelf, which drops away sharply.