Spolia opima

The spolia opima ("rich ") were the armour, arms, and other effects that an ancient Roman general stripped from the body of an opposing commander slain in single combat. The spolia opima were regarded as the most honourable of the several kinds of war trophies a commander could obtain, including enemy military standards and the peaks of warships.

For the majority of the city's existence, the Romans recognized only three instances when spolia opima were taken. The precedent was set in Rome's legendary history, when in 752 BC Romulus defeated and stripped Acro, king of the Caeninenses, following the Rape of the Sabine Women. In the second instance, Aulus Cornelius Cossus obtained the spolia opima from Lar Tolumnius, king of the Veientes, during Rome's semi-legendary Regal period. The third and most historically grounded occurred before the Second Punic War when Marcus Claudius Marcellus (consul 222 BC) stripped the Celtic warrior Viridomarus, a king of the Gaesatae.

In addition to these three cases, there is unclear but suggestive evidence that implies that Augustus' son-in-law Drusus Germanicus won the spolia opima from a Germanic king at some point during his campaigns in Germany (12 BCE–9 BCE), when he had expressly sought out enemy kings for single combat, thus becoming the fourth and final Roman to gain this honour.

The ceremony of the spolia opima was a ritual of state religion that was supposed to emulate the archaic ceremonies carried out by the founder Romulus. The victor affixed the stripped armor to the trunk of an oak tree, carried it himself in a procession to the Capitoline, and dedicated it at the Temple of Jupiter Feretrius.

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