Soon after becoming king, he was forced to defend his position against a brother, Hormizd, viceroy of the eastern provinces. In 283, exploiting Bahrām's preoccupations, the Roman emperor Carus invaded Mesopotamia unopposed and entered Ctesiphon, the Sāsānian capital. Carus' sudden death, however, forced the Romans to withdraw, and soon thereafter the overthrow of Hormizd made Bahrām secure. Numerous southern Persian rock sculptures depict Bahrām wearing his winged crown, and several include his queen. Because female portraits are rare in Sāsānian art, she is thought to have been a major dynastic personage.