Braun came to study Scandinavian and Germanic epics on the advice of Alexander Veselovsky.
He graduated from St. Petersburg University in 1885 (with a gold medal for his thesis on Beowulf) and was a lecturer at the Bestuzhev Courses.
His major writings, including an 1899 monograph on the relations between the Goths and Ancient Slavs, concern the history of Germanic peoples in Eastern Europe.
[2] He joined the staff of the Leipzig University in 1922 and published a paper in support of the Japhetic theory.
In 1933 Braun signed the Vow of allegiance of the Professors of the German Universities and High-Schools to Adolf Hitler and the National Socialistic State.