The cross was likely erected in the 12th century and served as an ecclesiastical boundary marker (
termonn). Reportedly, it was one of three similar structures, but it is the only one whose whereabouts are known today. the cross is therefore the "Cross of Baoth's daughter." Saint Inneenboy was the patron saint of the
Dál gCais. In 1937,
Adolf Mahr, Keeper of Irish Antiquities and Director of the
National Museum of Ireland, published a theory that associated the cross with the
Celtic double-heads from
Roquepertuse, France. In 1940, Joseph Raftery supported this theory, counting the Kilnaboy cross in the same category of
La Tène sculptures. Etienne Rynne, however, in an article on the Tau Cross in 1967, compared the craft style of the two carved heads with other works nearby – the immediate area offering three other examples of tau-croziers. He thus showed that the cross was in fact likely a boundary mark of the Romanesque period (12th century) and not a pagan idol of the early
Iron Age. ==Description==