DVINSK  , the

official name since 1893 of DuNABURG, a town and fortress of western Russia, in the government of Vitebsk, 162 m. by rail N.W. of the city of Vitebsk, on the right bank of the Dvina (Duna), in 550 53' N. and 26° 23' E., and at the intersection of two main railway lines—Riga–Smolensk and Vilna–St Peters-burg . It is the chief strategic position for the defence of the Dvina . It consists of four portions—the main town, or fortress, the old suburb, the new suburb, and on the left bank of the river the village of Griva . Among the industrial establishments are tanneries and breweries, saw-mills, flour-mills, brick and tile works and limekilns . The town is an important commercial centre, especially for flax, hemp, tallow and timber . The population increased from 25,764 in 186o to 72,231 in 1900, consisting chiefly of Jews (about 30,000), Lithuanians and Letts . Dunaburg was originally founded in 1278 by the Livonian Knights of the Sword, about 12 M. farther down the river than its present site, at a spot still known as the Old Castle or Stariy Zamok . In 1559 it was mortgaged by the grand-master of the Knights to Sigismund Augustus, king of Poland . Although captured in 1576 by Ivan the Terrible of Russia, it was again restored to Poland; and in 1582 Stephen Bathori, king of Poland, transferred the fortress to its present site . In the 17th century it was held alternately by the Swedes and the Russians . It was finally incorporated with Russia in 1772 011 the first division of Poland . In July 1812 the fete-de-pont was vainly stormed by the French under Oudinot, but a few weeks afterwards the town was captured by them under Macdonald .