As the power of the kingdom of Palmyra rose, the ruins of which are in what is now Syria, Vabalathus appropriated for himself the title of Augustus. Behind him his mother Zenobia was the mastermind of a series of battles won against various Roman detachments sent to depose this usurper. Aurelian finally took command of the situation and feigned a truce while launching a concerted attack against Egypt which was under Palmyra's control. When Egypt fell Palmyra lost its valuable trade routes and it was then a simple matter to regain control of the Syrian province. Both Vabalathus and Zenobia were captured and taken back to Rome but it's not recorded whether they were executed.
RIC 4, Cohen 3 AE Antoninianus Obv: IMCVHABALATHVSAVG; Radiate bust right.
Rev: IVENVSAVG; Hercules standing right holding club, lionskin, and three apples of the Hesperides, star in left field