Tribune, to Britain in 372–373 with an army in order to replenish troops there and made the noblemen Bitheridius and Hortarius commanders in his army although Hortarius was soon executed for conspiring with Macrian. Valentinian's Alamannic campaigns, however, were hampered by troubles first in Africa, and later on the Danube river. In 374 Valentinian was forced to make peace with Macrian because the Emperor's presence was needed to counter an invasion of Illyricum by the Quadi and Sarmatians. The Great Conspiracy In 367, Valentinian received reports from Britain that a combined force of Picts, Attacotti and Scots had killed the Comes litoris Saxonici Nectaridus and Dux Britanniarum Fullofaudes. At the same time, Frankish and Saxon forces were raiding the coastal areas of northern Gaul. The empire was in the midst of the Great Conspiracy – and was in danger of losing control of Britain altogether. Valentinian set out for Britain, sending Comes domesticorum Severus ahead of him to investigate. Severus was not able to correct the situation and returned to Gaul, meeting Valentinian at Samarobriva. Valentinian then sent Jovinus to Britain and promoted Severus to magister peditum. It was at this time that Valentinian fell ill and a battle for succession broke out between Severus, a representative of the army, and Rusticus Julianus, magister memoriae and a representative of the Gallic nobility. Valentinian soon recovered however and in 367 appointed his son Gratian as his co-Augustus in the west. Ammianus remarks that such an action was unprecedented. Jovinus quickly returned saying that he needed more men to take care of the situation. In 368 Valentinian appointed Theodosius as the new Comes Britanniarum with instructions to return Britain to Roman rule. Meanwhile, Severus and Jovinus were to accompany the emperor on his campaign against the Alamanni. Theodosius arrived in 368 with the Batavi, Heruli, Jovii and Victores legions. Landing at Rutupiæ, he proceeded to Londinium restoring order to southern Britain. Later, he rallied the remaining garrison which was originally stationed in Britain; it was apparent the units had lost their cohesiveness when Fullofaudes and Nectaridus had been defeated. Theodosius sent for Civilis to be installed as the new vicarius of the diocese and Dulcitius as an additional general. In 369, Theodosius set about reconquering the areas north of London; putting down the revolt of Valentinus, the brother-in-law of a vicarius, Maximinus. Subsequently, Theodosius restored the rest of Britain to the empire