Aulus Cornelius Cossus

Aulus Cornelius Cossus was a Roman politician and general who lived in the 5th century BC.

Aulus Cornelius Cossus was a member of the partician gens Cornelia. During the war against the Etruscan city of Veii, Cossus became one of only three Roman generals ever to be awarded the spolia opima for killing the enemy leader in single combat. According to Livy Cossus unhorsed the Veientes' King Lars Tolumnius and struck him down. After taking the linnen cuirass of Tolumnius' body he decapitated the corpse and put the head on a lance and paraded it in front of the enemy, who retreated in horror. Cossus donated the captured armour, shield and sword to the Temple of Jupiter Feretrius on the Capitoline Hill, where even in the day of Emperor Augustus it could be seen. In 428 BC Cossus was elected consul together with Titus Quinctius Poenus Cincinnatus.

Cossus was elected a consular tribune (tribunus militum consulari potestate) in 426 BC. According to Livy, Cossus held the command in the city while the other three tribunes (Caius Furius Pacilus Fusus, Marcus Postumius Albinus Regillensis and Titus Quinctius Poenus Cincinnatus) marched the army to Veii. There due to infighting and divided command they were defeated by the Veientes. Because of the defeat the public demanded the appointment of a dictator. After consultation of the augurs whether it was appropriate for a non consul to appoint a dictator, Aulus Cornelius Cossus, after receiving a positive reply, nominated Mamercus Aemilius Mamercinus as dictator, and was himself nominated by him as his master of the horse. Cossus later served as pontifex maximus.

Together with Lucius Furius Medullinus, Aulus Cornelius Cossus was elected to a second consulate in 413 BC, although both Diodorus Siculus and Cassiodorus state that Marcus Cornelius Cossus was elected.