The roots of theoretical physics in Bulgaria are examined thematically. Some physical scientific ideas created in Sofia University during the first half of 20 century are shown. They mark off the beginning of meteorology (Stayco Staycow), analytical mechanics (Ivan Tzenoff), ballistics (Kyrille Popoff), astronomy (Nicola Boneff), physical chemistry (Ivan N. Stranski) and classical dynamics (Georgi I. Maneff). Evaluations of the theory of Maneff are cited and the historical evidences about theoretical education and specialisation abroad are collected.

Keywords: history, theoretical physics, Bulgaria