Who was Saint Illogan?
In ancient times it was customary to dedicate churches to saints with whom a church had in some way been associated. Illogan is a Celtic personal name found both in Cornwall and Brittany, and Illogan is the name of a Celtic saint known both in Montgomeryshire and Brittany.

Boderlogan, a farm in Wendron, Cornwall, was spelt Bod-elugan in 1316, which means "the house of Illogan". A Saint Ilog is the patron saint of Hirnant in Powys, Wales, and the name occurs in several forms in that parish. Several early Welsh Kalenders contain his name.

When William of Worcester visited the Dominican Friary of Truro in 1378 he was told that the body of the saint was enshrined in Illogan Church, the original reference in Latin being Sanctus Illugham de Cornubia jacet prope Redruth, prope villam Truroburgh

St Illogan may once have had his own Feast Day, only to lose it after the Reformation when many were abandoned to reduce the number of holidays each year. The Feast Day of St Illogan is now held on St Luke's Day, possibly because the name of the evangelist somewhat resembles the old Celtic saint.