The Celtic tongue is a group of languages that originated in the British Isles. The four main languages are ERSE (4 letters), IRISH (5 letters), WELSH (5 letters) and GAELIC (6 letters). ERSE is the language spoken in Ireland, IRISH is the language spoken in Northern Ireland, WELSH is the language spoken in Wales and GAELIC is the language spoken in Scotland. All of these languages are part of the Celtic language family and share many similarities.