Magnus Maximus, Western Roman Emperor - Macsen, who died c. 388 AD

Came across a text referencing St. Augustine's letter 'Ad Orosium presbyterum contra Priscillianistas et Origenistas...', discussing heresies of Priscillianism and the text mentions this being named for a "Priscillian, the Bishop of Avila, from whom, though he was not its founder, the heresy takes its name, was charged with being a magician, and was executed at Treves in 385 A. D., by the order of Maximus the Usurper, at that time recognized as legitimate emperor in Gaul. St. Martin of Tours had tried to save Priscillian's life, but to no avail." - Jurgens, Wm. A, The Faith of the Early Fathers, v.3, p.144, Liturgical Press, Collegeville, MN, 1979.

This brought to mind the tale that Machsen Wledig and Elen 'Of the Hosts' had visited St. Martin at Tours.