During the reign of his father, Caracalla's mother Julia Domna had played a prominent public role, receiving titles of honour such as "Mother of the camp", but she also played a role behind the scenes helping Septimius administer the empire. Described as ambitious, Julia Domna surrounded herself with thinkers and writers from all over the empire. While Caracalla was mustering and training troops for his planned Persian invasion, Julia remained in Rome, administering the empire. Julia's growing influence in state affairs was the beginning of a trend of emperors' mothers having influence, which continued throughout the Severan dynasty.