Trajan probably remained in the region after the revolt was quashed, to engage with the Chatti who had sided with Saturninus, before returning the VII Gemina legion to Legio in Hispania Tarraconensis. In 91 he held a consulate with Acilius Glabrio, a rarity in that neither consul was a member of the ruling dynasty. He held an unspecified consular commission as governor of either Pannonia or Germania Superior, or possibly both. Plinywho seems to deliberately avoid offering details that would stress personal attachment between Trajan and the "tyrant" Domitianattributes to him, at the time, various (and unspecified) feats of arms. Rise to power Domitian's successor, Nerva, was unpopular with the army, and had been forced by his Praetorian Prefect Casperius Aelianus to execute Domitian's killers. Nerva needed the army's support to avoid being ousted. He accomplished this in the summer of 97 by naming Trajan as his adoptive son and successor, claiming that this was entirely due to Trajan's outstanding military merits. There are hints, however, in contemporary literary sources that Trajan's adoption was imposed on Nerva. Pliny implied as much when he wrote that, although an emperor could not be coerced into doing something, if this was the way in which Trajan was raised to power, then it was worth it. Alice König argues that the notion of a natural continuity between Nerva's and Trajan's reigns was an ex post facto fiction developed by authors writing under Trajan, including Tacitus and Pliny. According to the Augustan History, the future Emperor Hadrian brought word to Trajan of his adoption. Trajan retained Hadrian on the Rhine frontier as a military tribune, and Hadrian thus became privy to the circle of friends and relations with whom Trajan surrounded himself. Among them was the governor of Germania Inferior, the Spaniard Lucius Licinius Sura, who became Trajan's chief personal adviser and official friend. Sura was highly influential, and was appointed consul for third term in 107. Some senators may have resented Sura's activities as a kingmaker and éminence grise, among them the historian Tacitus, who acknowledged Sura's military and oratorical talents, but compared his rapacity and devious ways to those of Vespasian's éminence grise Licinius Mucianus. Sura is said to have informed Hadrian in 108 that he had been chosen as Trajan's imperial heir. As governor of Upper Germany (Germania Superior) during Nerva's reign, Trajan received the impressive title of Germanicus for his skilful