After Belisarius departed for Constantinople, he was succeeded as "magister militum Africae" by his "domesticus" (senior aide), the eunuch Solomon from Dara. The tribes of Mauri living in Byzacena and Numidia almost immediately rose up, and Solomon set out with his forces, which included allied Moorish tribes, against them. The situation was so critical that Solomon was also entrusted with civil authority, replacing the first prefect, Archelaus, in the autumn of 534. Solomon was able to defeat the Mauri of Byzacena at Mamma, and again, decisively, at the battle of Mt. Bourgaon in early 535. In the summer, he campaigned against Iaudas and the Aurasii, who were ravaging Numidia, but failed to achieve any result. Solomon then set about erecting forts along the borders and the main roads, hoping to contain the raids of the Moors.