Hermann Otto Erich Sasse was a German Lutheran pastor, theologian, and author. He was considered one of the foremost confessional Lutheran theologians of the 20th century.
Sasse was born on 17 July 1895 in Sonnewalde, Lower Lusatia, Germany, to Hermann Sasse, a pharmacist, and his wife Maria, née Berger. In 1913, he began reading theology and ancient philology at the University of Berlin. He was a German infantryman in World War I, in which he was one of only six men in his battalion to survive the trench warfare in Flanders.
Sasse began his career under the influence of the theological liberalism of his teachers, such as Adolf Harnack. He was ordained on 13 June 1920 in St Matthew's Church in Berlin and thereafter served several parishes in Brandenburg, He took the licentiate in theology in 1923. He spent a year as an exchange student at Hartford Theological Seminary in the United States, where he earned a master's degree. Sasse returned to Germany to take up a teaching position at University of Erlangen.
He married Charlotte Margarete Naumann on 11 September 1928 at St. Nicolai's Church in Oranienburg, Germany. They had three children together.