His father was Joseph Litten, the president of the Jewish community in Königsberg from 1899 to 1906.
He married Irmgard Litten from an established Lutheran family in Swabia, the daughter of Albert Wüst, a professor at the University of Halle-Wittenberg.
Fritz was born and raised Jewish, but converted to Lutheranism in order to further his career as a law professor.
[1] He was a nationalist conservative, and served in the army in World War I, earning the Iron Cross, 1st and 2nd Class.
A distinguished jurist and professor of Roman and civil law, he was dean of Königsberg's law school, later becoming rector of that institution.