BERTOLD (I442-1504), elector and archbishop of Mainz, son of George, count of Henneberg, was made archbishop of Mainz in 1484. He was an enemy of clerical abuses and a careful admin istrator of his diocese. Immediately after his election as arch bishop 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. During the reign of the emperor Frederick III. he had brought the question of administrative reform before the diet, and after Frederick's death, when he had become imperial chancellor, he was the leader of the party which pressed the neces sity for reform upon Maximilian at the diet of Worms in 1495. 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 150o established a council of regency (Reichs-regiment), and in 1502 persuaded the electors to form a union to uphold the reforms of 1495 and 1500. Bertold died on Dec. 21,1504. He 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).