He was most likely born in Palmyra, and an inscription at the Temple of Bel reveals his ancestry, where he is recorded as "The son of Septimius Ogeilu Maqqai".
[2] Like Odaenathus and many other important Palmyrene officials at the time, his family adopted the surname of the Severi as a sign of loyalty to the imperial throne.
[5][2] The inscription styles him as "The high priest Septimius Haddudan, illustrious senator, son of Septimius Ogeilu Maqqai, who had aided the army of Aurelian Caesar",[2] which shows that the priests of the Temple of Bel were probably among the first of the Palmyrenes to support the Emperor Aurelian and defy Zenobia.
[2] Although it is implied that he had helped the Romans in one way or another during the Palmyrene revolts, it is unknown how, why and when,[6] as the line giving the Seleucid date is damaged.
In the 1996 highly fictionalized Syrian soap opera, Al-Ababeed (The Anarchy), based on 3rd century Palmyra, the character of Elahbel in the show, the powerful, ruthless and treacherous Palmyrene courtier who betrays Zenobia and gives aid to the Romans, played by Salloum Haddad, appears to be based on Haddudan.