|Saint Eugene, Martyr and
Bishop, 5th Century
The Roman Martyrology lists 16 martyrs named Eugenius. One of them was the St. Eugene most likely pictured at left, who according to the Martyrology was decapitated by the Arian king Huneric:
Eodem die sancti Vindemialis, Episcopi et Martyris, qui, una cum sanctis Episcopis Eugenio et Longino doctrina et miraculis adversus Arianos decertans, a Rege Wandalorum Hunnerico jubetur variis tormentis affligi ac tandem capite obtruncari.Wikipedia's article on Huneric gives the year 484 for this event. No other "Saint Eugene" in the Martyrology is said to have been decapitated.
At left, Carlo Loth, The Martyrdom of St. Eugene, shows the saint both before and after the beheading. Behind him a soldier prepares to behead another of the bishops with the sword in his right hand. Presumably the cudgel in the hand of the man in the right edge of the painting represents one of the "various torments" in the account. Perhaps the man pointing to Heaven is Vindemialis.