This 1820 map of Livland Province is from a larger work, Geograficheskii atlas Rossiiskoi imperii, tsarstva Pol'skogo i velikogo kniazhestva Finliandskogo (Geographical atlas of the Russian Empire, the Kingdom of Poland, and the Grand Duchy of Finland), containing 60 maps of the Russian Empire. Compiled and engraved by Colonel V.P. Piadyshev, it reflects the detailed mapping carried out by Russian military cartographers in the first quarter of the 19th century. The map shows population centers (six gradations by size), postal stations, roads (four types), provincial and district borders, taverns, and customs houses. Distances are shown in versts, a Russian measure, now no longer used, equal to 1.07 kilometers. Legends and place-names are in Russian and German. The territory depicted on the map corresponds to the southern part of present-day Estonia and the northern part of present-day Latvia. In the 12th−13th centuries, a Catholic military order known as the Livonian Brothers of the Sword captured much of this region in the era of the Northern Crusades. This region borders Lake Peipus (Lake Chudskoye in Russian on this map), which was the site of the famous Battle on the Ice in 1242. This legendary clash, between the Teutonic Knights and the Russians from Novgorod, helped to establish Alexander Nevsky as the patron saint of Russia. This conflict set an effective border between the medieval Russian and German territories. In subsequent centuries, ecclesiastical German elites (later known as Baltic Germans) formed a landed nobility that enserfed the native Estonian and Latvian peasantry. Local German barons, inhabiting the castles and estates established by the Teutonic Knights, subsequently shared ruling status with the bishops and archbishops of Riga, Dorpat (present-day Tartu), and other regional cities in the Livonian Confederation. The Swedish kings conquered this entire area in the 16th century, and established a Lutheran culture in Swedish Livonia. The subsequent Livonian War between Russia, Sweden, and Poland-Lithuania led to further upheavals by the late 16th century. Peter the Great gained this region in the Great Northern War (1700−1721) with Charles XII of Sweden, after which it became part of the Russian Empire and known as Livland Province.