Deventer, city in the central Netherlands, in Overijssel Province, on the IJssel River, near Apeldoorn. An industrial center, the city has flour mills, machine shops, and plants producing carpets, chemicals, and textiles. Among the many medieval and Renaissance structures in Deventer are two churches—the Groote Kerk (Great Church), dating from the 8th century (later rebuilt), and the Romanesque Bergkerk, dating partly from the 13th century. The municipal library houses manuscripts from the 10th century onward. Deventer is of interest to scholars as the locale of the 14th-century religious movement connected with the Dutch preacher Gerhard Groote and as the scene of the boyhood of Desiderius Erasmus, the great humanist of the Renaissance. Population (2000) 83,883.