Naumachia

Naumachia, a Greek word signifying literally a naval battle; afterwards, among the Romans, a spectacle which consisted in the imitation of a naval battle. Julius Cæsar was the first to introduce a naumachia into Rome, 46 B.C., causing a portion of the Campus Martius to be dug to form a lake, on which the spectacle came off. Augustus also made an artificial lake near the Tiber for the same purpose, and Claudius employed Lake Fucinus, where on one occasion 19,000 combatants were engaged for this purpose. The combatants were for the most part either captives or condemned criminals. These naumachie were not sham-fights any more than were ordinary gladiatorial combats; both sides fought on in real earnest for dear life until one was utterly overpowered.