CÖTHEN, or Köthen, a town of Germany, in the duchy of Anhalt on the Ziethe, at the junction of several railway lines, 42 m. N.W. of Leipzig by rail. Pop. (1905) 22,978. It consists of an old and a new town with four suburbs. The former palace of the dukes of Anhalt-Cöthen, in the old town, has fine gardens and contains collections of pictures and coins, the famous ornithological collection of Johann Friedrich Naumann (1780–1857), and a library of some 20,000 volumes. Of the churches the Lutheran Jakobskirche (called the cathedral), a Gothic building with some fine old stained glass, is noteworthy. Besides the usual classical and modern schools (Gymnasium and Realschule) Cöthen possesses a technical institute, a school of gardening and a school of forestry. The industries include iron-founding and the manufacture of agricultural and other machinery, malt, beet-root sugar, leather, spirits, &c.; a tolerably active trade is carried on in grain, wool, potatoes and vegetables. Among others, there is a monument to Sebastian Bach, who was music director here from 1717 to 1723.

In the 10th century Cöthen was a Slav settlement, which was captured and destroyed by the German king Henry I. in 927. By the 12th century it had secured town rights and become a considerable centre of trade in agricultural produce. In 1300 it was burned by the margrave of Meissen. In 1547 the town was taken from its prince, Wolfgang (a cadet of the house of Anhalt), who had joined the league of Schmalkalden, and given by the emperor Charles V., with the rest of the prince’s possessions, to the Spanish general and painter, Felipe Ladron y Guevara (1510–1563), from whom it was, however, soon repurchased. Hahnemann, the founder of homoeopathy, lived and worked in Cöthen. From 1603 to 1847 Cöthen was the capital of the principality, later duchy, of Anhalt-Cöthen.