The Battle of the Bagradas River (the ancient name of the Medjerda), also known as the Battle of Tunis, was a victory by a Carthaginian army led by Xanthippus over a Roman army led by Marcus Atilius Regulus in the spring of 255 BC, nine years into the First Punic War. The previous year, the newly constructed Roman navy established naval superiority over Carthage. The Romans used this advantage to invade Carthage's homeland, which roughly aligned with modern-day Tunisia in North Africa. After landing on the Cape Bon Peninsula and conducting a successful campaign, the fleet returned to Sicily, leaving Regulus with 15,500 men to hold the lodgement in Africa over the winter.