This degree of severity might have been held by the Prussian authorities to be unnecessary, had Ewald been less hostile in his language. The violent tone of some of his printed manifestoes about this time, especially of his "Lob des Königs u. des Volkes", led to his being deprived of the "venia legendi" (1868) and also to a criminal trial, which, however, resulted in his acquittal (May 1869). Then, and on two subsequent occasions, he was returned by the city of Hanover as a member of the North German and German parliaments. In June 1874 he was found guilty of a libel on Otto von Bismarck, whom he had compared to Frederick the Great in "his unrighteous war with Austria and his ruination of religion and morality," to Napoleon III in his way of "picking out the best time possible for robbery and plunder." For this offence he was sentenced to undergo three weeks' imprisonment. He died in Göttingen in his 72nd year, of heart disease.