Political map of Europe & the Mediterranean 30 June 26 AD (Roman Clients in Germania): In 21 AD Arminius was assassinated in a pro-Roman plot, leading to the collapse of his alliance and the reduction of his tribe—the Cherusci—to a Roman client state. At around the same time, the Romans backed the creation of a number of client kingdoms among the tribes of the upper Danube, spreading their system of indirect rule across much of Magna Germania. It would be some 140 years before the Germans would again pose a serious threat to the Empire (Marcomannic Wars).