John H. Tietjen (June 18, 1928 – February 15, 2004) was a Lutheran clergyman, theologian, and national church leader in the United States.
The faculty's use of Historical-Critical Method for biblical interpretation was cast by conservatives as being at odds with the historic theological position of the LCMS.
Tietjen was accused of allowing the teaching of false doctrine, and he was suspended from his duties as seminary president in January 1974.
Seminex existed in St. Louis until August 1983, and on the campus of the Lutheran School of Theology at Chicago (LSTC) until December 1987.
Meanwhile, Tietjen and many of his supporters left the LCMS to form the more liberal Association of Evangelical Lutheran Churches (AELC).