In examining the horsemen on the Parthenon frieze, particularly those on the south side, several commentators have flirted more or less openly with the concept of a cavalry “uniform,” either for different tribes or for different festivals. Through an examination of relevant literature, small-scale art, and the Parthenon frieze itself, I argue that the idea is without strong foundation. Literature, vases, and small-scale reliefs indicate that cavalry dress was not prescribed at either state or tribal level but was the responsibility of each cavalryman. Variety rather than uniformity was the natural result. Even when we sense that artists are depicting cavalrymen as types, there is considerable variation in the detail of their dress, and there are significant differences between the small-scale depictions and the Parthenon frieze. The south frieze of the Parthenon does indeed distinguish ranks of riders by employing distinctive dress, but the north frieze employs a different method, concentrating upon foregrounding and pose. One cannot theorize from the south frieze alone. The degree to which the frieze may be used as a documentary source is called into question.