TILSIT, a commercial town of East Prussia and the capital of Prussian Lithuania, is situated on the left bank of the Memel or Niemen, 52 miles south-east of the town of Memel and 60 north-east of Konigsberg. The town is spacious, and has a number of handsome modern buildings, including a town-house, post-office, law-courts, and a large hospital. It contains three Protestant churches, a Roman Catholic church, and a Jewish synagogue. The manufactures include soap, leather, shoes, glass, and other articles, and there are iron-foundries and steam flour and saw mills. Tilsit carries on trade in timber, grain, hemp, flax, herrings, and other northern produce; but its trade with Russia, at one time considerable, has fallen off since the construction of the railway from Konigsberg via Insterburg and Gumbinnen to Kovno. The river is navigable beyond the town. The market-gardening of the neighbourhood deserves mention, and the annual horse-fair and markets are of considerable local importance. In 1783 the population was 8060; in 1880 it had increased to 21,400, and in 1885 to 22,428.

Tilsit, which received town-rights in 1552, grew up around a castle of the Teutonic order, known as the "Schalauner Haus," founded in 1288. It owes most of its interest to the peace signed here on 9th July 1807, the preliminaries of which were settled by the emperors Alexander and Napoleon on a raft moored in the Memel. The peace of Tilsit, which constituted the kingdom of Westphalia and the duchy of Warsaw, registers the nadir of Prussia's humiliation under Napoleon (see Prussia, (vol. xx. p. 11). The poet Max von Schenkeudorf (1784–1817) was born at Tilsit.