Odaenathus was described as Roman senator in the undated tomb inscription and Hairan I was mentioned with the same title in the 251 inscription . Scholarly opinions vary on the exact date of Odaenathus ' elevation to the position ; Gawlikowski and Jean Starcky maintain that the senatorial rank predate the Ras elevation . Udo Hartmann conclude that Odaenathus first became a Ras in the 240s then a senator in 250 . Another possibility is that the senatorial rank and lordship occurred simultaneously ; Odaenathus was chosen as a Ras following Gordian 's death , then after Philip the Arab concluded a peace with the Persians , the emperor ratified Odaenathus ' lordship and admitted him to the senate to guarantee Palmyra 's continuous subordination .