The authors consider the scientific heritage of A. A. Krotkov (1866–1945), a famous Saratov archaeologist and numismatists who was also a discoverer of the Golden Horde city of Mohshy. The researcher identified the city of Mohshy with the Narovchat settlement in the Penza province in his article “In Search of Mohshy” (1923). A.A. Krotkov used the data on archaeology, numismatics and historical geography for his scientific argumentation. The researcher led a number of archaeological excavations in Narovchat and in its neighborhood in 1925–27. He made an approximate plan of the city of Mohshy and reconstructed its history according to the results of these works. A.A. Krotkov believed that the city was built at the beginning of the reign of khan Uzbek (about 1313 AD). The city was the center of the ulus. The Mordva-Moksha people were the main population of the ulus. The city prospered in the middle of the 14th century. The long decline of the Mohshy started after the aggressive campaign of Tamerlane (1395). The authors conclude that, despite some errors, Krotkov’s works on the history of the Narovchat have scientific importance to this day.