Archbishop of Mainz (Mayence) 1111 to 1137. He was of the family of the Counts of Saarbrücken, and under both Henry IV and Henry V of Germany he held the office of imperial chancellor, discharging his duties with energy and skill. In 1110, as head of an embassy sent to Rome to arrange for the coronation of Henry V as Emperor (crowned king 6 January, 1099), he had much to do with bringing about the Treaty of Sutri, in which advantage was taken of the character of Pope Paschal II, formerly Abbot of Cluny, who was a saintly man, but no diplomat. A disagreement arising regarding the treaty, Henry subjected the Pope to a harsh imprisonment of two months. Fearing schism, the Pope finally granted Henry the privilege of conferring the ring and staff on bishops, providing they were elected by papal consent, and soon after he crowned Henry in St. Peter's at Rome (1111). Henry, according to compact, named Adalbert Archbishop of Mainz in reward for his part in the shameful intrigue against the Supreme Pontiff. From the day when, as Archbishop elect, he received the insignia of his office, Adalbert become a changed man. Whether this marvellous change was due to a realization of his sacred duties or to an awakening to the sacrilegious injustice of Henry's conduct at Rome, we cannot say. At any rate the ex-chancellor, lately so blindly zealous for the Emperor in right or wrong, became henceforth a brave and loyal defender of the Church and the Pope. In 1112 Henry V was excommunicated, and Adalbert fearlessly promulgated the sentence; whereupon the enraged Emperor cast him into a dark dungeon. After three years of cruel imprisonment had reduced him to a mere skeleton, the people of Mainz, rising in a body, forced Henry to release him. The episcopal consecration, delayed by his confinement, was then received at the hands of Otto, Bishop of Bamberg (1115). Later, when, under Pope Calixtus II, Adalbert was made a legate, Henry seized some pretext for attacking Mainz, whereupon Adalbert aroused the Saxon princes to arms. The two armies met, but arbitration prevented a battle. As a result, the Council of Worms (1122) was finally held, bringing to a close the long strife regarding Investitures. In 1125 Henry V was on his deathbed, and being without male issue sent the imperial insignia to his wife Matilda, daughter of Henry I of England. The politic Adalbert, ever on the alert to ward off any danger of a schism, induced Matilda to return the insignia, and called an assembly of princes, who chose as Henry's successor Lothair II the Saxon, afterwards crowned Emperor in Rome by Pope Innocent II (1133). Thus the Empire passed from the house of Franconia to that of Saxony, which had so long proved itself loyal to the cause of Rome. Adalbert died in 1137, having atoned for his early injustice by long years of faithful and efficient service in all that touched the interests of truth and the welfare of the Church.

ROHRBACHER, Hist. de l'église, XV; WILL, in Kirchenlex., 1, 194. IDEM, Regesten zür Gesch. der Mainzer Erzb. (Innsbruck, 1877), I; HUPERZ, De Adelberto Archiep. Mogunt. (Münster, 1855).

JOHN J. A' BECKET