Julia Avita Mamaea or Julia Mamaea (c. 182 or 192 AD – 21/22 March 235) was a Christian Syrian noblewoman and member of the Severus dynasty. She was the mother of the Roman emperor Alexander Severus and remained one of his chief advisers throughout his reign.Julia Avita Mamaea was the second daughter of Julia Maesa, a powerful Roman woman of Syrian descent, and the Syrian nobleman Gaius Julius Avitus Alexianus. Julia Maesa was the niece of Empress Julia Domna, the sister of Emperor Lucius Septimius Severus, and the sister of Julia Soaemias Bassiana. She was born and grew up in Emesa (present-day Homs, Syria), where her family was extremely influential. Julia's first husband was an unknown man who had previously been a consul, but died. Their only undisputed child, Severus Alexander, born to Arca in Caesarea on 1 October 208, may have been from this marriage, rather than from her second husband as Dio claimed. Arca married her second husband, the Syrian promagistrate Marcus Julius Gessius Marcianus in Caesarea (Arqa, Lebanon). When his cousin Emperor Caracalla died near Carrhae, Macrinus proclaimed himself emperor. Mamaea's mother Maesa and her sister Soaemias organized an uprising against Macrinus to make Soaemias' son Varius Avitus Bassianus (Elagabalus) emperor. In response, several individuals associated with Elagabalus were killed in Macrinus' camp, including Mamaea's husband, Gessius, in 218. Julia arranged for the education of her son Alexander before he became emperor of Rome. Alexander valued his mother's advice and followed what she told him. As an empress and advisor, Mamaea played an important role in the history of the Roman Empire and her memory lives on to this day.

Empress Juloa Mamaea, widow of Emperor Septimius Severus and mother of Emperor Caracalla, reigned alongside her son from 222 to 235. During this period, the coinage of the Roman Empire underwent significant changes. At the beginning of his reign, Mamaea continued the financial reform introduced by Caracalla. He significantly improved the quality of coinage and introduced new types of money, such as the antoninian, which became the main currency of the empire. During Mamaea's reign, images of the empress played an increasingly important role in coinage. Mamaea's gold and silver coins were almost always decorated with the portrait of the empress. This change reflected the growing power and influence of Mamaea in the empire. The coinage of Mamaea is evidence of the financial stability of the empire and the growing position of power of the empress. The most significant of the coins minted by Mamaea are the following: Gold solidi bearing the portrait of Mamaea and the inscription "Julia Mamaea Augusta " can be seen. Silver Antoninians with the portrait of Mamaea and the inscription "Julia Mamaea Augusta" or "Julia Augusta". Bronze denarius with the portrait of Mamaea and the inscription "Julia Mamaea Augusta" or "Julia Augusta". Coins minted by Mamaea still highly valued numismatic rarities today.