HENRY IV. (Ioso—IIo6), Roman emperor, son of the em peror Henry III. and Agnes, daughter of William V., duke of Guienne, was born on Nov. I1, io5o, chosen German king at Tribur in 1053, and crowned at Aix-la-Chapelle on July 17, In 1 o5 5 he was appointed duke of Bavaria, and on his father's death in 1056 inherited the kingdoms of Germany, Italy and Bur gundy. These territories were governed in his name by his mother who was compelled in 1062 to hand over her control to Anno, archbishop of Cologne, and to Adalbert, archbishop of Bremen. In March io65 Henry was declared of age, and in the following year married Bertha, daughter of Otto, count of Savoy.
In i o69 the king led expeditions against the Liutii, and against Dedo or Dedi II., margrave of a district east of Saxony; and soon afterwards quarrelled with Rudolph, duke of Swabia, and Berthold, duke of Carinthia. His struggle with Otto of Nordheim, duke of Bavaria, who was accused in io7o of being privy to a plot to mur der the king, ended in the duke's submission in 10 71. Henry aroused the hostility of the Thuringians by supporting Siegfried, archbishop of Mainz, in his efforts to exact tithes from them, and the enmity of the Saxons by ordering a restoration of all crown lands in Saxony, by ravaging the country to supply the needs of his courtiers, and by holding its duke Magnus a prisoner. In 1073 the Thuringians joined the Saxons, and the war, which lasted with slight intermissions until io88, exercised a potent influence upon Henry's fortunes elsewhere (see SAXONY). For Henry's dispute with Hildebrand (Pope Gregory VII.), his excommunication and his famous visit to Canossa see GREGORY VII.
Henry left Italy to find that in his absence Rudolph, duke of Swabia, had been chosen German king; and although Hildebrand had taken no part in this election, Henry sought to prevent the pope's journey to Germany, and tried to recover his former position. Though supported by most of the German bishops and by the Lombards and recognized in Burgundy, Bavaria and Fran conia, Henry suffered defeat at Mellrichstadt in i078 and at Flarchheim in io80. Gregory's attitude remained neutral, in spite of appeals from both sides, until March i o8o, when he again excommunicated Henry. At Henry's initiative, Gregory was de clared deposed on three occasions, and an anti-pope was elected in the person of Wibert, archbishop of Ravenna, who took the name of Clement III.
The death of Rudolph, the rival German king, in Oct. left the king at liberty to go to Italy early in I o8 i . He found considerable support in Lombardy ; placed Matilda, marchioness of Tuscany, the faithful friend of Gregory, under the imperial ban ; took the Lombard crown at Pavia ; and secured the recogni tion of Clement by a council. After two unsuccessful attacks, he took Rome in 1°82, and a treaty was concluded with the Romans, who agreed that the quarrel between king and pope should be de cided by a synod, and secretly bound themselves to induce the pope to crown Henry as emperor, or to choose another pope. The synod was a failure, and in March 1°84 Gregory was declared deposed and Clement was recognized by the Romans. On March 31, io84 Henry was crowned emperor by Clement, and received the patrician authority. His next step was to attack the fortresses still in the hands of the pope, but the advance of Robert Guiscard, duke of Apulia, compelled him to return to Germany.
Meanwhile the German rebels had chosen a fresh anti-king, Hermann, count of Luxemburg. In io86 Henry was defeated near Wiirzburg, but in io88 Hermann abandoned the struggle and the emperor was generally recognized in Saxony. Although Henry's power was in the ascendent, a few powerful nobles adhered to the cause of the new pope, Urban II. Among them was Welf, son of the deposed duke of Bavaria, whose marriage with Matilda of Tuscany rendered him formidable. The emperor accordingly returned to Italy in Togo, where Mantua and Milan were taken, and Pope Clement was restored to Rome.
Henry's first wife had died in i o8 7, and in 1 o89 he had married a Russian princess Praxedis, afterwards called Adelaide. Her conduct soon aroused his suspicions, and his own eldest son, Con rad, who had been crowned German king in 1087, was thought to be a partner in her guilt. Adelaide fled to Henry's enemies and brought charges against him ; and the papal party induced Conrad to desert his father and to be crowned king of Italy at Monza in io93. After five years of inactivity Henry returned to Germany where his position was stronger than ever. Welf had submitted and had been restored to Bavaria; the diet assembled at Mainz in 1098 declared Conrad deposed, and chose the emperor's second son, Henry, afterwards the emperor Henry V., as German king, and the crusade of 1096 had freed Germany from many turbulent spirits. But the younger Henry, in 1104, encouraged by the adhe rents of the pope, declared he owed no allegiance to an excom municated father. Saxony and Thuringia were soon in arms and in I105, the emperor became a prisoner in the hands of his son. A diet at Mainz in December compelled him to abdicate, but con trary to the conditions, he was detained at Ingelheim and denied his freedom. Escaping to Cologne, he entered into negotiations with England, France and Denmark, and was engaged in collecting an army when he died at Liege on Aug. 7, 1106.
After a licentious youth, Henry displayed much diplomatic ability, and his abasement at Canossa may fairly be regarded as a move of policy to weaken the pope's position at the cost of a per sonal humiliation to himself. He was a friend of the lower orders, was capable of generosity, and showed considerable military skill. Unfortunate in the troubles with which he had to contend, he ably resisted the pretensions both of the papacy and of the ambitious feudal lords of Germany.
The authorities are Lambert of Hersfeld, Annales; Bernold of Reichenau, Chronicon; Ekkehard of Aura, Chronicon; and Bruno, De bello Saxonico, all in the Monumenta Gersnaniae historica. Scrip tores, v. and vi. (1826-92) . An anonymous Vita Heinrici IV. was edited by W. Wattenbach (Hanover, 1876) . See G. Meyer von Knonau, Jahrbiicher des deutschen Reiches meter Heinrich IV. (Leip zig, 189o) ; H. Floto, Kaiser Heinrich IV. (Stuttgart, 1855) ; E. Kilian, Itinerar Kaiser Heinrichs IV. (Karlsruhe, 1886) ; K. W. Nitzsch, "Das deutsche Reich and Heinrich IV.," in the Historische Zeitschri f t, Band xlv. (Munich, 1859) ; H. Ulmann, Zum Verstandniss der sdchsischen Erhebung gegen Heinrich IV. (Hanover, 1886) , W. von Giesebrecht, Geschichte der deutschen Kaiserzeit (Leipzig, 1881-9o) ; B. Gebhardt, Handbuch der deutschen Geschichte (19o1) ; E. Hoehne, Kaiser Hein rich IV. (1906) ; C. Labarum, The Victory of Henry IV. at Canossa (1913) and B. Schmeidler, Kaiser Heinrich IV. and seine Helfer im Investiturstreit (1927). Further bibliography in Dahlmann-Waitz, Quellenkunde der deutschen Geschichte (Gottingen, 1894) ; and in Camb. Mediaeval Hist., vol. 5.