July 1: Saints Julius and Aaron, Martyrs

True Witnesses of the Gospel

The center of the veneration of Saints Julius and Aaron is Caerleon, a Celtic name meaning “City of the Legions” (Quadrata Legionum). Caerleon, located in southern Wales, was a fortress permanently occupied by the Second Augustan Legion from 75 to 431 AD.
The two were likely martyred during the Diocletian persecution, around the year 304.

A 9th-century document mentions two churches in Caerleon dedicated to the saints: one to Saint Julius, on the south bank of the River Usk, and the other to Saint Aaron, on the north bank. In the 12th century, the Book of Llandaff refers to a church or chapel called Merthir Jun et Aaron ("martyrdom" of Julius and Aaron), located in the “territory of the holy martyrs Julius and Aaron.” Furthermore, among the many sacred wells in Wales, one is dedicated to Saint Aaron, and a church dedicated to both saints also existed in Silchester.

Their liturgical memorial was originally set by Ado (around 860) for June 22, but Peter de Natalibus, between 1369 and 1372, moved it to July 1—likely to associate it with the feast of Aaron, the High Priest of the Old Testament. This date was later maintained in the Roman Martyrology.