The Religionsgeschichtliche Schule ("history of religions school", 19th century) had a profound influence on the study of Gnosticism. The Religionsgeschichtliche Schule saw Gnosticism as a pre-Christian phenomenon, and Christian gnosis as only one, and even marginal instance of this phenomenon. According to Wilhelm Bousset (1865–1920), Gnosticism was a form of Iranian and Mesopotamian syncretism, and Eduard Norden (1868–1941) also proposed pre-Christian origins, while Richard August Reitzenstein (1861–1931), and Rudolf Bultmann (1884–1976) also situated the origins of Gnosticism in Persia. Hans Heinrich Schaeder (1896–1957) and Hans Leisegang (1890–1951) saw Gnosticism as an amalgam of eastern thought in a Greek form.
The Religionsgeschichtliche Schule ("history of religions school", 19th century) had a profound influence on the study of Gnosticism. The Religionsgeschichtliche Schule saw Gnosticism as a pre-Christian phenomenon, and Christian gnosis as only one and even marginal instance of this phenomenon. According to Wilhelm Bousset (1865–1920), Gnosticism was a form of Iranian and Mesopotamian syncretism, and Eduard Norden (1868–1941) also proposed pre-Christian origins, while Richard August Reitzenstein (1861–1931), and Rudolf Bultmann (1884–1976) also situated the origins of Gnosticism in Persia. Hans Heinrich Schaeder (1896–1957) and Hans Leisegang (1890–1951) saw Gnosticism as an amalgam of eastern thought in a Greek form.