St. Viktor, with flag and shield. - martyr, according to tradition a Praefectus cohortis of a Cohort of the Theban Legion. He was executed in the 4th century in the amphitheater of Castra Vetera (Xanten) for refusing to sacrifice to the Roman gods (Wikipedia).
St. Mauritius - leader of the legendary Roman Theban Legion in the 3rd century, and one of the favorite and most widely venerated saints of that group
St. Gereon - may have been a soldier, was martyred at Cologne, allegedly by beheading, probably in the early 4th century
the statues of Maurice and Gereon are almost identical, with sword and shield.
AD SANCTOS MARTYRES
"Ad Sanctos Martyres" (at the holy martyrs) is the origin of the name Xanten.