Cantabri, ancient Iberian tribe thought to have a strong Celtic element; its people were subdued by the Romans after protracted campaigns beginning before 100 bc. Their homelands lay among the Cantabrian Mountains along the northern coast of Spain. Regarded as the fiercest people of the peninsula, they were finally subjugated by Rome in 19 bc. The Cantabri were originally divided into nine distinct clans; reorganization under the Romans reduced the number of tribal units to seven.