Celtic map. Celts or Kelts were an ethno-linguistic group of tribal societies in Iron Age and Medieval Europe who spoke Celtic languages and had a similar culture, although the relationship between the those elements remains controversial. Today, the term Celtic generally refers to the languages and respective cultures of Ireland, Scotland, Wales, Cornwall, the Isle of Man, and Brittany, also known as the Six Celtic Nations. These are the regions where four Celtic languages are still spoken.
