The title of "champion of Christ" (athleta Christi) was originally used for these saints, but in the late medieval period also conferred on contemporary rulers by the Pope.
In Late Antiquity, Christian writers of hagiography, prominently including Sulpicius Severus in his account of the heroic, military life of Martin of Tours, created a literary model that reflected the new spiritual, political, and social ideals of a post-Roman society.
In a study of Anglo-Saxon soldier saints (Damon 2003), J. E. Damon has demonstrated the persistence of Sulpicius's literary model in the transformation of the pious, peaceful saints and willing martyrs of late antique hagiography to the Christian heroes of the early Middle Ages, who appealed to the newly converted societies led by professional warriors and who exemplified accommodation with and eventually active participation in holy wars that were considered just.
[1] The Military Saints are characteristically depicted as soldiers in traditional Byzantine iconography from about the 10th century (Macedonian dynasty) and especially in Slavic Christianity.
Three equestrian saints, Demetrius, Theodore and George, are depicted in the "Zoodochos Pigi" chapel in central Macedonia in Greece, in the prefecture of Kilkis, near the modern village of Kolchida, dated to the 9th or 10th century.