Astyrius was the father-in-law of Merobaudes and belonged to an aristocratic family.
[3] He followed a military career: between 441 and 443 he is attested as dux or magister utriusque militiae.
At the beginning of his office he was in Gaul (probably in the capital city of the praetorian prefecture, Arelate), and Nicetius delivered a panegyric in his honour.
[6] A consular diptych produced by Astyrius in 449 is preserved at Liège.
The diptych shows Astyrius seated on a curule chair wearing complete consular regalia and the inscription Flavius Astyrius vir clarissimus[7] et inlustris[8] comes[9] ex magistro utriusque militiae consul ordinarius.