Louis the German crossed the Danube and again invaded Moravia in August 864. He besieged Rastislav "in a certain city, which in the language of that people is called Dowina", according to the "Annals of Fulda". Although the Franks could not take the fortress, Rastislav agreed to accept Louis the German's suzerainty. However, he continued to support the Frankish monarch's opponents. For instance, Louis the German deprived one Count Werner "of his public offices", because the count was suspected to have conspired with Rastislav against the king.