 A Lutheran, Sohm studied Law in Rostock, Berlin, Heidelberg and Munich between 1860 and 1864.His doctoral dissertation in 1864 at the University of Rostock was on Roman Law; he then worked on German legal history and devoted himself to ecclesiastical law.He lectured in German Law and Commercial Law at the University of Göttingen from 1866 to 1870, before being appointed professor at that university in 1870.