The word �Celt' comes from both Latin (Celtae) and Greek (Keltoi). It is because of the double source that the word's adjective form, 'Celtic', is pronounced in two different ways. For example, the name of the Glasgow football team, Celtic , is pronounced with a soft C...Seltic from the Latin, whereas the people named as Celts are usually pronounced with a hard C...Keltic from the Greek.
The original Celts were an Indo-European people in the Iron-Age, spread across the area from the British Isles in the north and Spain in the south to what is now Turkey. The Roman Empire absorbed them all as Britons, Gauls, Galatians and so on.
In modern-day Britain, people still described as Celts are highland Scots, Irishmen, Welshmen and Cornishmen.