The Empress Justina (370-388) is a central figure in the Valentinian dynasty (364-392), as well as one of the most important and influential empresses in Late Antiquity. Justina’s reign as empress spanned the majority of this period and her legacy reached well beyond into the fifth century. During her reign, Justina played a pivotal role in stabilizing and securing both her husband’s imperial legitimacy and her son’s imperial succession and security. During the usurpation of Magnus Maximus (383-388), Justina and Ambrose, Bishop of Milan, fought over control and influence of the Milanese basilica. This conflict has often been seen as a doctrinal dispute between Nicene and Arian Christians. However, if we understand that her goal was securing Valentinian II’s reign and defeating Magnus Maximus, we can conclude that Justina was a pragmatic and effective empress. Ultimately, Justina set a standard for imperial women and their role in Church politics. Her legacy impacted not only later fifth century women, but also the representation of Helena as an empress. Ultimately, I argue that imperial women exerted real influence in the late fourth century. Furthermore, my analysis of the sources reveals the influence of late antique imperial women by looking beyond gendered stereotypes. In order to do this, I focus on the reign of the Empress Justina and her role during the basilica conflict with the Bishop Ambrose. Through a reanalysis of this conflict, I suggest alternative explanations for Justina’s actions and motivations. Accordingly, I conclude that Justina had a lasting legacy on the depiction of imperial women in the late fourth and fifth centuries and became a model for imperial women’s engagement with bishops and ecclesiastical politics.