ASCHAFFENBURG, a town in the government of Lower Franconia, in the kingdom of Bavaria, at the confluence of the Aschaffa with the Maine, near the foot of the Spessart-Wald. Its chief buildings are the Johannisburg, built (1605-14) by Archbishop Sweikard of Kronberg, which contains a library, with a number of incunabula, a collection of engravings and paintings ; the StOkirche, or cathedral, founded in 980 by Otto of Bavaria, in which are preserved various monuments by the Vischers, and a sarcophagus, with the relics of St Margaret (1540); the Capuchin hospital ; a theatre, which was formerly the house of the Teutonic order ; and several mansions of the German nobility. The town, which has been remarkable for its educational establishments since the 10th century, has a gymnasium, lyceum, seminarium, and other schools. The grave of Clemens Brentano (d. 1842) and his brother Christian (d. 1851) is in the churchyard near the Wennebach gate; and Wilhelm 1-leinse (d. 1803) is buried in the town. Cloth and stained paper are the chief manufactures ; and the trade is principally in wood. The 10th and 23d Roman legions had their station at Aschaffenburg, and on the ruins of their castrum the Frankish mayors of the palace built a castle. Bonifacius erected a chapel to St Martin, and founded a Benedictine monastery. The stone bridge over the Maine was built by Archbishop Willigis in 989. Adalbert increased the importance of the town in various ways about 1122. In 1292 a synod was held there, and in 1474 an imperial diet, preliminary to that of Vienna, in which the famous concordats were decided, which have therefore been sometimes called the Aschaffenburg concordats. The town suffered greatly during the Thirty Years' War, being alternately held by the various belligerents. In 1812-9, King Louis built himself a country house to the west of the town, called the Pompeianum, from being an imitation of the house of Castor and Pollux at Pompeii. In 1866 the Prussians inflicted a severe defeat on the Austrians in the neighbourhood. Population, 9212.

The principality of Aschaffenburg, deriving its name from the city, comprehended an area of 336 geographical square miles. It formed part of the electorate of Mentz, and in 1803 was made over to the archchancellor, Archbishop Charles of Dalberg. In 1806 it was annexed to tho grandduchy of Frankfort ; and in 1814 was transferred to Bavaria, in virtue of a treaty concluded 19th June between that power and Austria. Conjointly with Lower Franconia, it now forms a circle of the kingdom of Bavaria.