Duchy of, a small state of Germany, bounded on the N. by Rhenish Prussia, W. by the same and the River Rhine, S. by Hesse-Darmstadt, and E. by the Frankfort district, Hesse-Darmstadt, and the Prussian district of Wetzlar; between N. Lat. 49° 56' and 50° 48', and E. Long. 7° 30' and 8° 35'. There are besides two detached portions, the one in Hesse-Darmstadt, the other in Hesse-Cassel; and including these, the entire territory has an area of 1810 square miles. The surface of the country is hilly, and in many parts highly picturesque. A range of hills, called the Taunus, in the S., between the rivers Lahn and Main, attain the height of from 2600 to 2800 feet; while another range in the northern part of the duchy, called the Westerwald, rises to the height of about 2000 feet. The Rheingau or Rhine district, noted for its fruitfulness and mild climate, is situated between the Main and the Rhine, to the S. of the Taunus Hills. The chief rivers are, the Rhine, forming the west boundary, and here about 2500 feet wide; and its tributaries the Lahn and Main. The former traverses the centre portion of the duchy, and the latter constitutes its southern frontier for part of its course. Several small lakes occupy the more level parts of the country; while as many as 153 mineral wells are known to exist here. Agriculture and mining are the chief branches of industry carried on. In some parts, especially on the Westerwald, the soil is mostly devoted to pasturage. Rye is the chief crop in the higher districts; while excellent wheat is grown in the lower situations, especially on the banks of the Lahn and Aar. Spelt is produced to a considerable extent, and barley is found almost everywhere, excepting on the Westerwald. The other products are oats and buckwheat, potatoes, rapeseed, flax, succory, tobacco, garden fruits, and grapes. The last form one of the staples of the duchy, which possesses the most famous vine district on the Rhine. It includes, among others, the vineyards of Johannisberg, Rußheim, Markebrunn, and Geisenheim, and that of Hochheim on the Main. The entire state usually produces wine to the amount of 1,020,000 gallons, of which about three-fourths are from the Rhine district alone.

Of a total area of 1,158,143 acres in Nassau, 493,421 are under forests, 433,684 under tillage, 121,136 meadows, 66,051 pasture, 9598 vines, 4612 gardens, 4041 domains, 769 lakes, and 24,831 waste land, roads, &c. In 1852 the crops were 691,072 qrs. potatoes, 148,982 qrs. rye and buckwheat, and 91,144 qrs. wheat and spelt; and in 1855 there were 195,541 cattle, 136,487 sheep, 44,780 swine, 26,794 goats, 12,020 horses, and 15,097 bee-hives.

Mining is the next most important branch of industry in Nassau. The minerals found include silver, iron, lead, copper, and manganese; but of these, iron is by far the most abundant. It is worked in the valleys of the Lahn and Dill, and the amount produced is, of raw iron, about 12,500 tons annually; of cast iron, about 3500 tons; and of bar iron 3500 tons. The lead mines produce about 170 tons, the copper about 150 tons, and the silver 11,000 oz. annually. With the exception of those connected with metals, the manufactures of Nassau are unimportant. They consist of linen and woollen goods, leather, earthenware, and paper; besides tobacco, oil, spirits, beer, and potash. The trade of the duchy is carried on by means of the rivers Rhine, Main, and Lahn; and by the Frankfort, Castel, and Wiesbaden Railway. The imports include, among other articles, colonial products, salt, cottons, and fancy goods; and the exports, wine, fruit, minerals, cattle, paper, and mineral water. The duchy is a member of the Germanic confederation, to which it sends two representatives, and belongs to the Zollverein, or trade union. The government is a limited monarchy, in the hands of the duke, assisted by two chambers of administration. The upper chamber consists of an unlimited number of members belonging to the royal family, nobility, and upper classes; while the lower house is formed of twenty-four members, returned from a like number of electoral districts.

All religions are tolerated in Nassau, but the full rights of citizenship are only accorded to evangelical Protestants and Roman Catholics. The former denomination is under the Bishop of Wiesbaden, and the latter under the Bishop of Limburg. The military force amounts to 3498 men, of whom 4542 form the contingent to the Germanic confederation.

Education is imparted to the people by means of elementary and real schools. There were in 1854, 708 of the former, with 992 teachers, and 10 of the latter. In Wiesbaden, the capital, a realgymnasium has also been established in connection with the preparatory and middle burgh schools, but no university has as yet been founded in the duchy. There are several normal schools and seminaries of Evangelical and Catholic theology, and a military academy. The public library of Wiesbaden contains from 50,000 to 60,000 volumes; and there is a museum in the same town devoted to antiquities. Two literary associations have been established, one for history and antiquities, the other for natural philosophy. There is also a stadt theatre in the town. In 1849 thirteen newspapers were published in Nassau.

The budget for 1827 estimates the revenue of the state at L288,397, and the expenditure at L376,043. The national debt amounts to L651,000. Of the revenue, about L6800 is raised from the duty on mineral water, and L8900 from that on the baths, which are very numerous here. The mineral wells are chiefly in the possession of the duke, and form a valuable property. In 1856 the total population numbered 432,039 persons, of whom 225,681 were Protestants, 198,960 Catholics, 6927 Jews, 341 German Catholics, and 130 Mennonites. Wiesbaden, the capital, contains 16,000 inhabitants. The duchy derives its name from the castle of Nassau, built by the counts of Laurenburg in the beginning of the twelfth century. In 1255 Walram IV. and Otho, the sons of Henry the Rich, divided the territory between them. The former took the earldoms of Nassau, Idstein, and Weilburg, and became the founder of the present family of Nassau. The descendants of Otho, on the other hand, became the earls of Dillenburg and Siegen, and the founders of the House of Nassau-Orange, to which William III. of England belonged. The counts of the older line soon made considerable additions to their territory by acquiring, among others, the lordships of Mehrenberg and Gleiberg. In 1605, after repeated changes, Lewis II., a member of the Nassau-Weilburg family, became sole master of all the lands in the possession of the Walram line. At his death, however, in 1625, the family was divided into the three branches of

—1st, Saarbruck, divided in the next generation into two branches, called Saarbruck-Saarbruck and Saarbruck-Usingen, both of which were again united in 1735, but became extinct in 1797, and the land devolved on the present line; 2d, Idstein, which became extinct in 1721; and 3d, Weilburg, on which all the states devolved, and since 1816 have formed but one principality. During the French revolution the city of Saarbruck, with its territory upon the left bank of the Rhine, was seized by the republicans. It then comprehended 430 square miles of land, with 53,000 inhabitants; for which, at the pacification in 1803, it received an indemnification of 750 square miles and 93,000 inhabitants, which were added to the canton of Usingen. The Count of Weilburg had lost on the left bank of the Rhine 170 square miles and 19,000 inhabitants, for which he received on the other side of that stream a territory of 330 square miles, with 37,000 inhabitants. At the period when Napoleon instituted the confederation of the Rhine in 1806, the whole of these families had been united in the person of the existing prince, who then received, in addition to the former territories which he possessed, a tract of land of 650 square miles, with 84,500 inhabitants, and at the same time the title of Duke was conferred upon the reigning prince.