Although of very ancient origins, the city of Viterbo became a real urban center in the Etruscan era. The Etruscan name of the city, Surina, was due to the presence, according to their beliefs, of the God Suri. The city soon expanded until the Roman period when it took the name of Sorrina Nova, becoming an important Latin center.

With the fall of the Roman Empire, the Lombards settled in the territory and created the Castrum Viterbii to strengthen the defense of their kingdom. During the Middle Ages the importance of the city continued to grow and, in 1145, it was even chosen as the papal seat by Eugene III.