Marcus Julius Gessius Bassianus^[1] (flourished 3rd century) was a Magister (master) in the Arval Brethren during the reign of Roman emperor Caracalla who ruled from 212 until 217.^[1]

Bassianus seems to be linked to the Julii and the Bassiani.^[2] From his name, could point to him as a possible son of the Syrian Roman nobles Marcus Julius Gessius Marcianus and Julia Avita Mamaea,^[3] being a possible brother of Roman emperor Alexander Severus^[4] and his sister, Theoclia.^[4][5] If this is correct, Bassianus was a relation to the Royal family of Emesa and the Severan dynasty of the Roman Empire.^[6]

Bassianus was not a known Priest of the cult of Elagabalus.^[7] Although he was a Roman Priest, was unable to attend the ceremonies of the Arval Brethren in Rome, probably due to Bassianus being based in the East.^[4]