Application of GIS Technologies in Studying the Early History of the Cossacks on the Territory of the Republic of Mordovia

The article shows the use of GIS technologies in studying the early history of the Cossacks in the Republic of Mordovia. As a result, the following maps were built: fortifications on the territory of the modern Republic of Mordovia in the XVII century; fortifications on the territory of the Russian state in the XVI-XVII centuries; territories covered by the uprisings led by S. Razin and E. Pugachev.