Conversation so far:
Where does Celtic art come from?
The Early Medieval art of Britain and Ireland is what Celtic art evokes for much of the general public. Celtic art also includes the Pictish art of Scotland.
What are the influences of Celtic art?
Archaeologists identified various cultural traits of these peoples, including styles of art, and traced the culture to the earlier Hallstatt culture and La Tène culture.

Question: What was the Hallstatt culture?
Self-contained rewrite: What was the Hallstatt culture that archaeologists traced the culture of Celtic art to?