In 209 BC, during the Second Punic War, Circeii was one of twelve Latin colonies to refuse any more military contributions towards Rome[6] and in 204 it was severely punished as a result,[7] by furnishing double the greatest number of foot soldiers they had ever provided and 120 horsemen, all chosen from the wealthiest of the inhabitants, and to be sent out of Italy. Also an annual tax was imposed.
In September 1975 the so called Circeo massacre took place in San Felice Circeo, the murder and rape of two young women which received significant media attention in Italy.