FREDERICK I. (c. I123-1190), Holy Roman emperor, called "Barbarossa" or "Redbeard" by the Italians, was the son of Frederick II. of Hohenstaufen, duke of Swabia, and Judith, daugh ter of the Welf Henry IX., duke of Bavaria. When his father died in 1147 Frederick became duke of Swabia, and immediately afterwards accompanied his uncle, the German king Conrad III., on his disastrous crusade, during which he won the complete con fidence of the king. In 1152 the dying king advised the princes to choose Frederick as his successor to the exclusion of his own young son. Frederick was chosen German king at Frankfurt on March 5, 1152, and crowned at Aix-la-Chapelle on the 9th, owing his election partly to his personal qualities, and partly to the fact that he united in himself the blood of the rival families of Welf and Waiblingen.
The new king saw clearly that the restoration of order in Germany was a necessary preliminary to the enforcement of the imperial rights in Italy. Issuing a general order for peace, he was prodigal in his concessions to the nobles. Abroad Frederick de cided a quarrel for the Danish throne in favour of Svend, or Peter as he is sometimes called, who did homage for his kingdom, and negotiations were begun with the East Roman emperor, Manuel Comnenus. About this time he obtained a divorce from his wife Adela, on the ground of consanguinity, and made a vain effort to obtain a bride from the court of Constantinople. On his accession Frederick had communicated the news of his election to Pope Eugenius III., but neglected to ask for the papal confirmation. But a treaty was concluded between king and pope at Constance in March 1153, by which Frederick promised in return fur his coronation to make no peace with Roger I. king of Sicily, or with the rebellious Romans, without the consent of Eugenius, and gen erally to help and defend the papacy.
The journey to Italy made by the king in 1154 was the pre cursor of five other expeditions which engaged his main energies for 3o years, during which the subjugation of the peninsula was the central and abiding aim of his policy. He was crowned em peror at Rome on June 18, 1155. He left Italy in the autumn of 1155 to prepare for a new and more formidable campaign. Dis order was again rampant in Germany, especially in Bavaria, but general peace was restored by Frederick's vigorous measures. Bavaria was transferred from Henry II. Jasomirgott, margrave of Austria, to Henry the Lion, duke of Saxony ; and the former was pacified by the erection of his margraviate into a duchy, while Frederick's step-brother Conrad was invested with the Palatinate of the Rhine. On June 9, 1156 the king was married at Wi.irzburg to Beatrix, daughter and heiress of the dead count of Upper Bur gundy, Renaud III., when Upper Burgundy or Franche Comte, as it is sometimes called, was added to his possessions. An expedition into Poland reduced Duke Boleslaus IV. to submission, after which Frederick received the homage of the Burgundian nobles at Besan con in Oct. 1157.
In June 1158 Frederick set out upon his second Italian ex pedition, during which imperial officers called podestas in the cities of northern Italy, captured revolted Milan, and the long struggle began with pope Alexander III., who excommunicated the emperor on March 2, During this visit Frederick sum moned the doctors of Bologna to Roncaglia in November 1158, and as a result of their inquiries into the rights belonging to the kingdom of Italy he obtained a large amount of wealth. Returning to Germany towards the close of 1162, Frederick prevented a conflict between Henry the Lion, duke of Saxony, and a number of neighbouring princes, and severely punished the citizens of Mainz for their rebellion against archbishop Arnold. In 1163 his plans for the conquest of Sicily were checked by a powerful league against him provoked by the exactions of the podestas and the enforcement of the rights declared by the doctors of Bologna. Frederick had supported an anti-pope Victor IV. against Alexan der, and on Victor's death in 1163 a new anti-pope called Paschal III. was chosen to succeed him. At a diet at Wurzburg in May 1165 he took an oath, followed by many of the clergy and nobles, to remain true to Paschal and his successors. A temporary alli ance with Henry II., king of England, the magnificent celebra tion of the canonization of Charlemagne at Aix-la-Chapelle, and the restoration of peace in the Rhineland, occupied Frederick's attention until Oct. 1166, when he made his fourth journey to Italy. Having captured Ancona, he marched to Rome, stormed the Leonine city, and procured the enthronement of Paschal, and the coronation of his wife Beatrix; but the sudden outbreak of a pestilence destroyed the German army and drove the emperor to Germany. During the next six years the imperial authority was asserted over Bohemia, Poland and Hungary. Friendly relations were entered into with the emperor Manuel, and a better under standing was sought with Henry II., king of England, and Louis VII., king of France.
In 1174, Frederick made his fifth expedition to Italy. The cam paign was a complete failure. The refusal of Henry the Lion to bring help into Italy was followed by the defeat of the emperor at Legnano on May 29, 1176, when he was wounded and believed to be dead. He concluded with Alexander the treaty of Venice (Aug. 1177), and at the same time a truce with the Lombard league was arranged for six years. Frederick, loosed from the papal ban, recognized Alexander, and in July 1177 knelt before him and kissed his feet. The possession of the vast estates left by Matilda, marchioness of Tuscany, and claimed by both pope and emperor, was to be decided by arbitration, and in Oct. 1178 the emperor was again in Germany. Henry the Lion was deprived of his duchy, and sent into exile ; a treaty was made with the Lom bard league at Constance in June 1183 ; and Frederick's son Henry was betrothed in 1184 to Constance, daughter of Roger I., king of "Sicily, and heiress of the reigning king, William II. This be trothal, which threatened to unite Sicily with the Empire, made it difficult for Frederick, when during his last Italian expedition in 1184 he met Pope Lucius III. at Verona, to establish friendly relations with the papacy. The question of Matilda's estates was left undecided ; and Lucius had refused to crown Henry or to recognize the German clergy who had been ordained during the schism. Frederick then formed an alliance with Milan, where the emperor, who had been crowned king of Burgundy, or Arles, at Arles on July 3o, 1178, had this ceremony repeated (Jan. 27, 1186); while his son Henry was crowned king of Italy and mar ried to Constance, who was crowned queen of Germany.
The quarrel with the papacy was continued with the new pope Urban III., and open warfare was begun. But Frederick was re called to Germany by the news of a revolt raised by Philip of Heinsberg, archbishop of Cologne, and instigated by the pope. Hostilities were checked by the death of Urban and the election of a new pope as Gregory VIII. In 1188 Philip submitted, and immediately afterwards Frederick joined the Third Crusade. He left Regensburg in May 1 189 at the head of a splendid army, and having overcome the hostility of the Eastern Roman emperor Isaac Angelus, marched into Asia Minor. On June io, 1190, Fred erick was either bathing or crossing the river Calycadnus (Geuksu), near Seleucia (Selefke) in Cilicia, when he was drowned. The place of his burial is unknown, and the legend which says he still sits in a cavern in the Kyffhauser mountain in Thuringia waiting until the need of his country shall call him, is now thought to refer, at least in its earlier form, to his grandson, the emperor Frederick II. He left by his wife, Beatrix, five sons, of whom the eldest afterwards became emperor as Henry VI.
Frederick encouraged the growth of towns, easily suppressed the few risings against his authority, and took strong and success ful measures to establish order in Germany. His power rested upon his earnest and commanding personality, and also upon the support which he received from the German church, the possession of a valuable private domain, and the care with which he exacted feudal dues from his dependents. Even in Italy, though his gen eral course of action was warped by wrong prepossessions, he in many instances showed exceptional practical sagacity in dealing with immediate difficulties and emergencies. From the beginning, however, he treated the Italians, as indeed was only natural, less as rebellious subjects than as conquered aliens.
In appearance Frederick was a man of well-proportioned, medium stature, with flowing yellow hair and a reddish beard. He delighted in hunting and the reading of history, was zealous in his attention to public business, and his private life was unimpeach able. Carlyle called him "a terror to evil-doers and a praise to well-doers in this world, probably beyond what was ever seen since." The principal contemporary authority for the earlier part of the reign of Frederick is the Gesta Friderici imperatoris, mainly the work of Otto, bishop of Freising. This is continued from 1156 to 116o by Rahewin, a canon of Freising, and from i i 6o to 117o by an anonymous author. The various annals and chronicles of the period are to be found in the Monumenta Germaniae historica. Scriptores (Hanover and Berlin, 1826-92) ; many valuable documents are found in the Mona menta Germaniae selecta, vol. iv., edited by M. Doeberl (Munich, 1889-90).
See also, J. Jastrow, Deutsche Geschichte im Zeitalter der Hohen staufen (1893) ; W. von Giesebrecht, Geschichte der deutschen Kaiser zeit, vol. iv. (Brunswick, 1877) ; H. von Biinau, Leben and Thaten Friedrichs I. (Leipzig, 1872) ; H. Prutz, Kaiser Friedrich I. (Dantzig, 1871-74) ; C. Peters, "Die Wahl Kaiser Friedrichs I." in the For schungen zur deutschen Geschichte, vol. xx. (Gottingen, 1862-86) ; W. Gundlach, Barbarossalieder (Innsbruck, 1899) . For a complete bibli ography see Dahlmann-Waitz, Quellenkunde der deutschen Geschichte (Gottingen, 1894), and U. Chevalier, Repertoire des sources historiques du moyen age, vol. iii. (19o4). See further W. Stubbs, Germany in the Early Middle Ages (1908), and Germany in the Later Middle Ages (1908).