Reuss, a river of Switzerland, tributary to the Aar, rising in the canton of Uri, near Mt. St. Gothard, within the small district where the Rhine, Rhône, and Ticino also have their source. It flows, fed by glaciers, in a northerly direction into the lake of Lucerne, and after leaving it follows a winding course, at first N. N. W. to the junction of the Emme, then N. E., and then crosses in a N. N. W. direction the canton of Aargau, joining the Aar at Windisch, east of Brugg. The total length of the river is about 100 m. Above Lake Lucerne it falls 4,500 ft., with many magnificent cascades; below it is navigable. The new road (built 1820-'32) over the St. Gothard crosses the Reuss eight times, one of the bridges being the celebrated Devil's bridge. (See Devil's Bridge).
Reuss, a territory of central Germany, between lat. 50° and 51° N, and lon. 11° and 13° E., enclosed by Saxe-Meiningen, Prussian Saxony, Saxe-Weimar, Altenburg, the kingdom of Saxony, and Bavaria; area, 443 sq. m.; pop. in 1871, 134,126, nearly all Protestants. It consists of two unequal portions, separated by the southern part of Weimar. It is a part of what was formerly known as Voigtland, mostly hilly, and traversed by the upper courses of the White Elster and Saale. Cattle and sheep are reared, and linen, woollen, and cotton are manufactured. The territory forms now two sovereign principalities of the German empire, Reuss-Greiz and Reuss-Schleiz. The former division (area, 123 sq. m.) is the patrimony of the elder branch of the reigning family; its capital is Greiz, on the Elster. The latter (area, 320 sq. m.), which is ruled by the younger line, comprises the principalities of Schleiz, Lobenstein-Ebersdorf, and Gera, the capital being Schleiz. The house of Reuss had its origin in the 12th century. All the male members of the princely family have from the beginning been named Henry, at first distinguished by surnames and afterward by numbers, the elder line beginning a new series after reaching C. (100), and the younger with each century.
The present reigning princes (1875) are Henry XXII. of the elder line, son of Henry XX., and Henry XIV. of the younger line, son of Henry LXVII.