CONRAD III. 0093-1152), German king, second son of Frederick I., duke of Swabia, and Agnes, daughter of the emperor Henry IV., was the first king of the Hohenstaufen family. His father died in 05, and his mother married secondly Leopold III., margrave of Austria. In III5 his uncle the emperor Henry V. ap pointed him duke of Franconia. In '10, together with his elder brother Frederick II., duke of Swabia, he was left by Henry as regent of Germany, and when the emperor died in '125 he became titular king of Burgundy, or Arles. In 1126 he took part in the war between his brother Frederick and the new king, Lothair the Saxon, and was chosen king in opposition to Lothair on Dec. 18, '127. Hastening across the Alps he was crowned king of Italy at Monza in June '128, and in spite of the papal ban was generally acknowledged in northern Italy. The rival popes, Innocent II. and Anacletus II., both declared against him; the Romans repudiated him ; and after failing to seize the extensive possessions left by Matilda, marchioness of Tuscany, he returned to Germany in '132. He continued the struggle against Lothair tili Oct. '135, when he submitted, was pardoned, and recovered his estates. In 1136 he accompanied the imperial forces to Italy in the capacity of stand ard-bearer, and sought to win the favour of Pope Innocent II.
In Dec. 1137 Lothair died, and some of the princes met at Co blenz and chose Conrad for a second time as German king on March 7, 1138, in presence of the papal legate. Crowned at Aix-la Chapelle six days later, he was acknowledged at Bamberg by several of the South German princes; but his position could not be strong while Henry the Proud, the powerful duke of Bavaria and Saxony, refused his allegiance. Attempts at a peaceful settle ment of this rivalry failed, and Henry was placed under the ban in July 1138, when war broke out in Bavaria and Saxony. The king was unable to make much headway, in spite of the death of Duke Henry, which occurred in Oct. '139; and his half-brother Leopold IV., margrave of Austria, to whom Bavaria had been entrusted, was defeated by Henry's brother Welf, afterwards duke of Spoleto and margrave of Tuscany. Conrad captured the fortress of Weins berg from Welf in Dec. 114o, and is said to have allowed‘ the women to leave the town, each with as much of her property as she could carry on her back. To his surprise, so the story runs, each woman came out bearing on her back a husband, a father or brother who thus escaped the conquerors. Peace was made at Frankfort in May 1142, when Henry the Lion, son of Henry the Proud, was confirmed in the duchy of Saxony, while Bavaria was given to Conrad's stepbrother Henry Jasomirgott, margrave of Austria, who married Gertrude, the widow of Henry the Proud.
Affairs in Italy demanded the attention of the king, as Roger I., king of Sicily, had won considerable authority on the mainland and refused to recognize the German king, whose help Pope Lucius II. implored against the rebellious Romans. This state of affairs drove Conrad into alliance with the East Roman emperor, Manuel Comnenus, who in 1146 married his stepsister; but the condition of Germany prevented the contemplated campaign against Roger. The solitary success amid the general disorder in the empire was the expedition undertaken in '142 by Conrad into Bohemia, where he restored his brother-in-law Ladislaus to this throne. An at tempt, however, to perform the same service for another brother in-law, also called Ladislaus, who had been driven from his Polish dukedom, ended in failure. Disorder was rampant in Saxony, Bavaria and Burgundy; and in 1146 war broke out between the Bavarians and the Hungarians. A term was placed to this con dition of affairs by the preaching of Bernard of Clairvaux, and the consequent departure of many turbulent nobles on crusade. In Dec. '146 the king himself took the cross, secured the election and coronation of his young son Henry as his successor, appointed Henry I., archbishop of Mainz, as his guardian, and set out for Palestine in the autumn of 1147. Marching with a large and splendid army through Hungary, he reached Asia Minor, where his forces were decimated by disease and by the sword. Stricken by illness, Conrad returned to Constantinople at Christmas '147. but in March '148 set out to rejoin his troops. Having shared in the fruitless attack on Damascus, he left Palestine in Sept. 1148 and passed the ensuing winter at Constantinople, where he made fresh plans for an attack on Roger of Sicily. He reached Italy by sea; but the news that Roger had allied himself with Louis VII., king of France, and his old opponent Welf of Bavaria, compelled him to return hastily to Germany. He was obliged to neglect re peated invitations from the Romans, who sent him a specially urgent letter in Ito, and consequently never received the imperial crown.
Conrad died on Feb. 15, '152, at Bamberg, where he was buried. By his wife, Gertrude, daughter of Berenger, count of Sulzbach, he had two sons, the elder of whom, Henry, died in ii5o. Passing over his younger son Frederick on account of his youth, he ap pointed as his successor his nephew Frederick III., duke of Swabia, afterwards the emperor Frederick I.
See Otto of Freising, "Chronicon," in the Monumenta Germaniae historica. Scriptores, Band xx. (Hanover and Berlin, 1826-92). The best modern authorities are O. von Heinemann, Lothar der Sachse und Konrad III. (Halle, 1869) ; W. von Giesebrecht, Geschichte der deutschen Kaiserzeit, Band iv. (Brunswick, 1877) ; L. von Ranke, Weltgeschichte, achter Teil (Leipzig, 1887-88) ; W. Bernhardi, Konrad III. (Leipzig, 1883) ; J. Jastrow, Deutsche Geschichte im Zeitalter der Iii. (Leipzig, 1883) ; J. Jastrow, Deutsche Geschichte im Zeitalter der Hohenstaufen (Berlin, 1893).