Quintus Clodius Hermogenianus Olybrius (floruit 361-384) was a Roman politician, praefectus urbi of Rome in 368–370 and Roman consul in 379. Olybrius has been characterized as belonging to "the breed of flexible politicians who did well both under Valentinian and under Gratian."

He reached the rank of vir clarissimus, then consularis of Campania (before 361 he is attested as patron of Formia), proconsul of Africa Province (361), praefectus urbi of Rome (369-370), Praetorian prefect of Illyricum, Praetorian prefect of the East, and consul in 379. He died between 384 and 395.

During his office as praefectus urbi, which was generally calm and balanced, he arrested two suspected poisoners. He led the investigations, but he got ill and they passed to the praefectus annonae, Maximinus. He was then succeeded by Publius Ampelius.

In his consulate he was posterior to his colleague, the poet Ausonius, because he was the younger prefect. Ausonius had been in fact appointed Praetorian prefect of Gaul in late 377. Olybrius had been appointed prefect of Illyricum by emperor Gratian probably at the beginning of 378, in the wake of the preparations for the war against the Goths in Thracia that led to the defeat and death of emperor Valens in the Battle of Adrianople in the August of that year.

It is also known that Olybrius was in Sirmium when he was appointed consul by Gratian, who also had already conferred upon Olybrius the Praetorian prefecture of the East.

Quintus Aurelius Symmachus records a trial in which he was a judge. A land-owner called Scirtius had been dispossessed of his property and had complained to Symmachus, who had then issued a decree giving the land back to Scirtius. Symmachus tells that he discovered that Olybrius was behind this misappropriation and that some of agents had tried to avoid the restitution of the stolen property even kidnapping people and bribing witnesses. Thus Olybrius is depicted as violent and greedy. This view is somehow confirmed by Ammianus Marcellinus' description of Olybrius' office as prefect: the historian, in fact, describes Olybrius as overly-interested in luxury.

Gift med
Juliana av Anicii, född 335 i Roma, Lazio, Italien, död 395 i Roma, Lazio, Italien.

Barn:
Proba av Anicii, född 355, död 432