Alexander Severus Severus Alexander ( ; 1 October 208 – 18 or 19 March 235 ) was Roman Emperor from 222 to 235 . Alexander was the last emperor of the Severan dynasty . He succeeded his cousin Elagabalus upon the latter ' s assassination in 222 , and was ultimately assassinated himself , marking the epoch event for the Crisis of the Third Century — nearly fifty years of civil wars , foreign invasion , and collapse of the monetary economy . Alexander was the heir apparent to his cousin , the eighteen - year - old Emperor who had been murdered along with his mother by his own guards , who , as a mark of contempt , had their remains cast into the Tiber river . He and his cousin were both grandsons of the influential and powerful Julia Maesa , who had arranged for Elagabalus ' acclamation as emperor by the famous Third Gallic Legion . It was the rumor of Alexander ' s death that triggered the assassination of Elagabalus and his mother . As emperor , Alexander ' s peace time reign was prosperous . Assessment of military conflict against the rising Sassanid Empire is mixed , though the Sassanid threat was checked . However , when campaigning against Germanic tribes of Germania , Alexander attempted to bring peace by engaging in diplomacy and bribery . This apparently alienated many in the legions and led to a conspiracy to assassinate and replace him . Persian and German wars . On the whole , however , the reign of Alexander was prosperous until the rise , in the east , of the Sassanids . Of the war that followed there are various accounts . According to Herodian , the Roman armies suffered a number of humiliating setbacks and defeats , while according to the Historia Augusta as well as Alexander ' s own dispatch to the Roman Senate , he gained great victories . Making Antioch his base , he marched at the head of his troops towards Ctesiphon , but a second army was destroyed by the Persians , and further losses were incurred by the retreating Romans in Armenia . Nevertheless , although the Sassanids were checked for the time , the conduct of the Roman army showed an extraordinary lack of discipline . In 232 there was a mutiny in the Syrian legion , who proclaimed Taurinus emperor . Alexander managed to suppress the uprising , and Taurinus drowned while attempting to flee across the Euphrates . The emperor returned to Rome and celebrated a triumph in 233 . The following year he was called to face German invaders in Gaul , who had breached the Rhine frontier in several places , destroying forts and over - running the countryside . Alexander mustered his forces , bringing legions from the eastern provinces , and crossed the Rhine into Germany on a pontoon bridge . Initially on the advice of his mother , he attempted to buy the German tribes off , so as to gain time . Whether this was a wise policy or not , it caused the Roman legionaries to look down on their emperor as one who was prepared to commit unsoldierly conduct . Herodian says " in their opinion Alexander showed no honourable intention to pursue the war and preferred a life of ease , when he should have marched out to punish the Germans for their previous insolence " . These circumstances drove the army to look for a new leader . They chose Gaius Iulius Verus Maximinus , a Thracian soldier who had worked his way up through the ranks . Death . Following the nomination of Maximinus as emperor , Alexander was assassinated ( on either 18 or 19 March 235 ) , together with his mother , in a mutiny of the Legio XXII " Primigenia " at Moguntiacum ( Mainz ) while at a meeting with his generals . These assassinations secured the throne for Maximinus . The death of Alexander is sometimes seen as the end of the Principate system established by Augustus . Although the " Principate " continued in theory until the reign of Diocletian , Severus Alexander ' s death signalled the beginning of the chaotic period known as the Crisis of the Third Century which brought the empire to near collapse . Legacy . Alexander was the last of the Syrian emperors . Under the influence of his mother , he did much to improve the morals and condition of the people , and to enhance the dignity of the state . His advisers were men like the famous jurist Ulpian , the historian Cassius Dio and a select board of sixteen senators ; a municipal council of fourteen assisted the urban prefect in administering the affairs of the fourteen districts of Rome . Excessive luxury and extravagance at the imperial court were diminished . Upon his accession he reduced the silver purity of the denarius from 46 . 5 % to 43 % — the actual silver weight dropping from 1 . 41 grams to 1 . 30 grams ; however , in 229 he revalued the denarius , increasing the silver purity and weight to 45 % and 1 . 46 grams respectively . The following year he decreased the amount of base metal in the denarius while adding more silver – raising the silver purity and weight again to 50 . 5 % and 1 . 50 grams . Also during his reign taxes were lightened ; literature , art and science were encouraged ; the lot of the soldiers was improved ; and , for the convenience of the people , loan offices were instituted for lending money at a moderate rate of interest . In religious matters Alexander preserved an open mind . It is said that he was desirous of erecting a temple to Jesus , but was dissuaded by the pagan priests . He allowed a synagogue to be built in Rome , and he gave as a gift to this synagogue a scroll of the Torah known as the Severus Scroll . Marriage . Alexander was married three times . His most famous wife was Sallustia Orbiana , " Augusta , " whom he married in 225 . He divorced and exiled her in 227 , after her father , Seius Sallustius , was executed after being accused of attempting to assassinate the emperor . Another wife was Sulpicia Memmia . Her father was a man of consular rank ; her grandfather ' s name was " Catulus " .