The article concerns biography and scientific work of Russian historian and publicist, Professor A. S. Madzharov. The author examines main stages of his academic activity, and highlights his contribution to the studying Russian historiography of the XIXth – the early XXth centuries, in particular A. P. Shchapov’s works. Considering by today’s standards, the author reveals basic values of A. P. Shchapov’s concept, and his studies on history of the Russian Orthodox Church schism, country council and regional theory, physical and anthropological theory. The author outlines that A. S. Madzharov has always considered scientific works of A. P. Shchapov whithin the context of principal research directions in Russian history. The author reveals polemical points in A. S. Madzharov’s publications and up-to-date schoolbooks, which contain substantial errors in the sections, covering Russian historiography of the XIXth – the early XXth centuries. The author presents A. S. Madzharov as a professional historian, scientific forums fascilitator, publicist, journalist, and a man of many accomplishments.