The first complete biography of the holy Prince Dovmont of Pskov, who defended the Russian land from the invasions of the Livonian Order and Lithuania for thirty years (1266–1299), named by the Russian historian S.F. Platonov, along with Alexander Nevsky and Daniil Galitsky, “hero of the 13th century”, canonized by the Russian Orthodox Church. The book also provides a complete description of the Teutonic Order of Crusaders - the main opponent of the Russian principalities in the 13th century, provides many sources speaking about the creation of the Lithuanian state by Prince Mindovg, describes the relationship between Novgorod and Pskov in the 13th century, publishes the Life of Dovmont, written by his contemporary, and the Abridged Pskov a chronicle compiled in 1831 by Metropolitan Evgeny (Bolkhovitinov) and telling about the history of Pskov from 862 to the Patriotic War of 1812.