He was born 22 March 1822 in Zistersdorf, Austria, son of the medical doctor Carl August Braun.

In 1849 he succeeded Ignaz Semmelweis as assistant to professor Johann Klein at the hospital's first maternity clinic, a position he held until 1853.

In 1853, after Braun became a Privatdozent, he was appointed ordinary professor of obstetrics in Trient and vice-director of the Tiroler Landes-Gebär- und Findelanstalt.

[5] In 1867–1871 he was appointed dean of the medical faculty, and in the academic year 1868/69 was made rector of the University of Vienna.

[9] These results suggest that Braun continued, assiduously, to require hand disinfection before attending women and did not let mortality return to the high levels before Semmelweis introduced the chlorine washings.