Johann Karl August Musäus (29 March 1735 – 28 October 1787) was a popular German author and one of the first collectors of German folk stories, most celebrated for his Volksmärchen der Deutschen (1782–86), a collection of German fairy tales retold as satires.
Born in Jena on 29 March 1735, the only son of Joseph Christoph Musäus, a judge. In 1743 his father became a councillor and police magistrate in Eisenach, and the young Musäus moved to live with his godfather and uncle Dr. Johann Weißenborn in Allstedt, who was entrusted with his education and treated Musäus like a son. He continued living with his uncle until he was nineteen years old, even when his uncle became general superintendent of Eisenach in 1744, a move which brought him to the same city as his parents again.
Musäus entered the University of Jena in 1754 to study theology (probably the choice of his godfather rather than his own), and was admitted into German Society around this time, a sign of more than ordinary merit. He received a Master's degree after the usual three and a half years of study, to add to the degree he had received honoris causa ten years earlier on 13 July 1747, and returned to Eisenach to wait for an appointment in the Church, which he was now licensed for. Despite preaching well, he was not especially devoted to religion, and received no appointment; when after several years he was offered a vacancy as pastor in the nearby countryside, the locals objected on the grounds that "he had once been seen dancing." This finished his hopes of a career in the church, and at the age of twenty-five he became an author of satire.
From 1760–62 Musäus published in three volumes his first work, Grandison der Zweite (Grandison the Second), afterwards (in 1781–82) rewritten and issued with a new title, Der deutsche Grandison (The German Grandison). The object of this book was to satirize Samuel Richardson's hero Sir Charles Grandison, who had many sentimental admirers in the Holy Roman Empire.