The son of George,
Count of Henneberg and Johanna, daughter of Count
Philipp I of Nassau-Weilburg was educated at the University of Erfurt. He entered the ecclesiastical profession and, after passing through its lower stages, from 1472 on was a member of the Mainz cathedral chapter, dean from 1475. On May 20, 1484 he was elected archbishop, confirmed by
Pope Innocent VIII on September 20, 1484. He was made imperial chancellor in 1486 in return for supporting the election of
Maximilian I. As a follower of
Nicholas of Cusa and the ideas of
Renaissance humanism, 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 of Habsburg as
King of the Romans.
Imperial Reform Henneberg is most remembered as an advocate of administrative reform in the Empire, including the implementation of the
Ewiger Landfriede (eternal public peace) to put an end to internal
feuds, secured by the jurisdiction of an
Imperial Chamber Court. As a member of the electoral college and
archchancellor he had brought this question before the
Reichstag diet during the reign of
Emperor Frederick III. At first his proposals came to nothing, but he continued the struggle at a series of diets and after Frederick's death, he was the leader of the party which pressed the necessity for reform upon Frederick's son Maximilian at the
Diet of Worms in 1495, where the
Ewiger Landfriede was declared. He also urged the
Imperial States to emulate the courage and union of the
Swiss Confederacy and gained a temporary victory when the 1500
Reichstag at
Augsburg established a council of regency (
Reichsregiment) under his guidance, making the Emperor "no more than an honorary figurehead" while the real power in the Empire was with Henneberg and the other prince-electors. Though he persuaded the electors to form a union to uphold the reforms of 1495 and 1500, the
Reichsregiment was abolished by Maximilian in 1502, defeating Henneberg's Electoral League, which had not managed to gain the trust of the Empire's other princes. The following year, he returned the imperial seal, signifying his defeat. Henneberg died on December 21, 1504. He is buried at
Mainz Cathedral where a magnificent monument perpetuates his memory. ==Notes==