" I had chosen the fifteenth day of July, the day that Roman Knights go out crowned with olive wreaths to honor the Twins in a magnificent horseback procession:from the Temple of Mars they ride through the main streets of the City, circling back to the Temple of the Twins, where they offer sacrifices. The ceremony is a commemoration of the battle of Lake Regillus which was fought on that day over three hundred years ago. Castor and Pollux came riding in person to the help of a Roman army that was making a desperate stand on the lake-shore against a superior force of Latins; and ever since then they have been adopted as the particular patrons of the knights. "

― Robert Graves , Claudius the God and His Wife Messalina (Claudius, #2)