The Roman Festivals of the Period of the Republic An...

But Livy[1322] gives the Ides of July as the day of dedication, and a difference of learned opinion has arisen[1323]. July 15, B.C. 496, is the traditional date of the battle of Lake Regillus, and the temple was dedicated B.C. 484—the result of the Consul’s vow in that battle[1324]. Mommsen infers that Livy confused the date of the dedication with that of the battle, and that Jan. 27 is right. Aust and others differ, and refer the latter date to a restoration by Tiberius, probably in A.D. 6[1325]. The mistake in Livy is easy to explain, and Mommsen’s explanation seems sufficient[1326]. Three beautiful columns of Tiberius’ temple are still to be seen at the south-eastern end of the Forum, near the temple of Vesta, and close to the Iacus Juturnae, where the Twins watered their steeds after the battle[1327].

The very early introduction of the Dioscuri into the Roman worship is interesting as being capable of unusually distinct proof. They must have been known long before the battle of the Regillus; and they took a peculiarly firm hold on the Roman mind, as we see from the common oaths Edepol, Mecastor, from their representation on the earliest denarii[1328], from their connexion with the equites throughout Roman history, and from the great popularity of their legend, which was reproduced in connexion with later battles[1329]. The spread of the cult through Southern Italy to Latium and Etruria (where it was also a favourite) is the subject of a French monograph[1330].