Tropaion

A Roman tropaeum from the Dacian Wars (Trajan's Column 113 AD), note the tree trunk with arm-like branches and the heaped armor and weapons at its base
A Roman tropaeum in process of erection in the presence of male and female captives, detail from the Gemma Augustea, circa 20-30 AD
A fully erected Roman tropaeum with shackled and addorsed seated man and woman Sarmatian captives (the woman on the right with head resting on hand, perhaps representing the defeated "Sarmatia") tied to base, Dupondius from reign of Emperor Marcus Aurelius, AD 161-180

A tropaion (Greek: τρόπαιον, Latin: tropaeum), from which the English word "trophy" is derived, was a monument erected to commemorate a victory over one's foes by the ancient Greeks and later, by the Romans. The armour of the defeated foe would be hung upon the monument. Originally, the location of the monument was the battlefield where the commemorated victory took place. Initially, the typical monument was constructed out of a living tree with lateral branches, or it was constructed in the shape of one. After construction, the tropaion was dedicated to a deity in thanksgiving for the victory. Some images of tropaion show many weapons and shields heaped below the armor hoisted upon the monument. In later times, pairs of lances, banners, or stakes set crosswise might be used instead of the tree format.