The Celts were an Indo-European people who by 500 B.C. had spread across what is now France, Italy, Portugal, Spain, and the British Isles, and by 200 B.C. they had expanded as far as present-day Bulgaria and Greece. When the Romans conquered much of Europe (about 300 B.C.), many Celts were absorbed into the Roman Empire. However, those Celts living in Ireland, Scotland, Wales, southwest England, and Brittany (in northwestern France) were able to maintain their cultures, and it is in these regions that people of celtic origin still live today.