The Castra Praetoria was the location of several important events in the history of Rome. It was to this camp that Claudius was brought after the murder of his nephew Caligula to become the first emperor to be proclaimed by the Praetorians. Here too was where the Praetorian Guard auctioned off the imperial title after their murder of the emperor Pertinax. On March 28 193 AD Titus Flavius Claudius Sulpicianus was within the barracks trying to calm the troops when he began to offer a donative if they would support his candidacy for the throne. Meanwhile, Didius Julianus also arrived at the camp, and since his entrance was barred, shouted out offers to the guard. After hours of bidding, Sulpicianus promised 20,000 sesterces to every soldier; Julianus, fearing that Sulpicianus would gain the throne, then offered 25,000. The guards closed with the offer of Julianus, threw open the gates of the camp, and proclaimed him emperor.Cassius Dio, LXXIV, 11.1-5 This was also the site of the slaying of the Emperor Elagabalus, and his mother Julia Soaemias by the Praetorians in 222 AD. Then in 238 AD, the barracks were attacked by the citizens of Rome who were in revolt against the emperor Maximinus Thrax.
