BERTOLD (1442–1504)  , elector and archbishop of Mainz, son of George, count of Henneberg, entered the ecclesiastical profession, and after passing through its lower stages, was made archbishop of Mainz in 1484 . He appears to have been a firm supporter of law and order, an enemy of clerical abuses and a careful administrator of his diocese . Immediately after his election as archbishop he began to take a leading part in the business of the Empire, and in 1486 was very active in securing the election of Maximilian as Roman king . His chief work, however, was done as an advocate of administrative reform in Germany . During the reign of the emperor Frederick III. he had brought this question before the diet, and after Frederick's death, when he had become imperial chancellor, he was the leader of the party which pressed the necessity for reform upon Maximilian at the diet of Worms in 1495• His proposals came to nothing, but he continued the struggle at a series of diets, and urged the Germans to emulate the courage and union of the Swiss cantons . He gained a temporary victory when the diet of Augsburg in 1500 established a council of regency (Reichsregiment), and in 1502 persuaded the electors to form a union to uphold the reforms of 1495 and 1500 . The elector died on the 21st of December 1504 . Bertold was a man of great ability and resourcefulness, and as a statesman who strove for an ordered and united Germany was far in advance of his age . See J . Weiss, Berthold von Henneberg, Erzbischof von Mainz (Freiburg, 1889) .