(Latin: Moguntiacum; French: Mayence)
City in Rhine-Hesse and former principality of the Holy Roman Empire.
Originally a Celtic settlement, Mainz became a Roman camp, 38 B.C.
Christianized about the second century, it was made an archiepiscopal see in 780.
The principality grew in size until it extended (on both sides of the Rhine) over an area of 3,200 square miles, representing a large ecclesiastical administration.
In 863 the office of Archchancellor of Germany was conferred on the archbishop, and in 1263 he was appointed one of the seven electors of the emperor and convener of the electoral college.
Mainz became a free imperial city, 1244, and the leader of the formation of the League of Rhenish Towns, 1254.
During the Thirty Years War the Swedes conquered the city in 1631, and the French in 1644 and 1688.
The electorate was secularized in 1803, the territory being divided among France, Prussia, Hesse, and other provinces.
The city possesses a Romanesque cathedral begun in 975, destroyed by fire, and restored in the 12th, 13th, and 14th centuries.
It contains the tombs of three electoral princes, Saint Boniface, and Frauenlob the Minnesinger.
The university (founded, 1477) and the Gothic church of Saint Stephen (1257-1328) are other noteworthy buildings.
New Catholic Dictionary