After the death of Charlemagne and his successor Louis the Pious, the eastern part of his extensive empire became the Holy Roman Empire and was ruled by various successor dynasties. Included among these was the Hohenstaufen Dynasty (1138–1254), of which the first emperor was called Frederick.
1. Frederick I Barbarossa
Frederick Barbarossa (r. 1155–1190) was elected Holy Roman Emperor in 1152 and crowned by Pope Adrian IV in 1155. Tall, ruddy, and imposing, he inspired fierce loyalty among his vassals. A central aim of his reign was to restore imperial authority in Italy, where power had fragmented among semi-independent communes. The wealthy Lombard cities—especially Milan—resisted his rule. Barbarossa campaigned in Italy six times, combining siege warfare, diplomacy, and harsh reprisals. In 1162, he sacked and destroyed Milan, scattering its population among four nearby villages and shocking even contemporaries. But in 1176, the Lombard League, a coalition of northern Italian cities quietly backed by Pope Alexander III, defeated him at the Battle of Legnano. The Peace of Constance in 1183 then confirmed the cities’ practical autonomy in return for nominal recognition of imperial overlordship.
Barbarossa subsequently turned his energies toward Germany and the east. In 1189, already in his late sixties, he took the cross for the Third Crusade and led a vast German army across Anatolia. In June 1190, he drowned crossing the Saleph River in Cilicia—whether thrown from his horse or attempting to swim, no chronicle agrees. His army turned back, giving rise to the eventual legend that he was not dead but sleeping beneath a tall mountain, waiting to wake and restore the empire in its hour of need.
2. Frederick II, Stupor Mundi, the Wonder of the World (1194–1250)
Born in Italy in 1194, Frederick II was the son of Emperor Henry VI and grandson of Frederick I, orphaned and raised by papal guardians in the cosmopolitan court of Palermo, Sicily, a crossroads of civilizations where Arab astronomers and physicians worked alongside Norman barons and Greek monks. Frederick absorbed it all, grew up speaking six languages (Arabic among them), and from childhood was immersed in a culture of inquiry, tolerance, and aesthetic refinement. He was one of the most intellectually extraordinary rulers in European history. His court at Palermo was a center of scientific translation and philosophical debate. He founded the University of Naples in 1224, conducted experiments on digestion, vision, and animal behavior, and published a detailed study of falconry and avian anatomy, still remarkable for its precision. His brilliant court at Palermo blended Norman, Arabic, and Jewish elements in a culture full of the warm south. He was witty and entertaining in several languages. He kept a harem guarded by black eunuchs, had dancing girls and an Arab chef, and maintained a menagerie of elephants, camels, lions, leopards, and a giraffe, which he famously gave as a gift to the Sultan of Egypt. He founded towns and industries; encouraged scholarship, poetry, and mathematics; and wrote the first classic medieval textbook on falconry.
In 1228, Frederick launched the so-called Sixth Crusade. He was, at the time, under excommunication by Pope Gregory IX, who had grown furious at Frederick’s repeated delays in departing, which violated a vow he had taken when crowned. Frederick sailed anyway, but instead of fighting, he negotiated a ten-year truce that granted Christian’s access to Jerusalem, Bethlehem, and Nazareth. He then walked into the Church of the Holy Sepulcher and crowned himself King of Jerusalem—a gesture of breathtaking audacity, since no pope was present to perform the ceremony. The Patriarch of Jerusalem placed the city under interdict; Christian clergy fled; and Muslim guards stood watch over the Christian holy sites!
Gregory IX and later Innocent IV regarded Frederick as a threat and political rival—a ruler who seemed to place his reasoning above papal respect, employed Muslims in his army and administration, and was rumored to be a skeptic or even an atheist. He was excommunicated several times, and the papacy even launched crusades against him. Frederick responded with unusual sophistication, articulating an early vision of secular imperial authority independent of Church sanction. His later years were consumed by revolts in Germany and Italy and relentless papal opposition. In 1250, he developed severe dysentery and died at his hunting lodge in southern Italy. He was buried in Palermo Cathedral. His heirs were eliminated within two decades: his son Manfred fell at the Battle of Benevento in 1266, and his grandson Conradin was executed in Naples in 1268.
3. Frederick III (1415–1493)
Frederick III was the first Holy Roman Emperor from the House of Habsburg, having first been the duke of several Austrian provinces. He was an effective ruler who organized the empire into a single state. Crowned Holy Roman Emperor in 1452, he was described as wanting to conquer the world while remaining seated. He is now viewed as having been successful in his ability to sit out difficult political situations, prevail over and outlive his opponents, and sometimes inherit their lands. He fought several wars against the Ottoman Empire and unsuccessfully attempted to gain control of Hungary and Bohemia. He was defeated in the Austro–Hungarian War (1477–1488) by Matthias Corvinus, who managed to maintain residence in Vienna until his death. He has been regarded as the true founder of the Habsburg imperial power.
Frederick’s health began to decline in February 1493. During Lent, he developed pain in his left leg, likely caused by arteriosclerosis. On 8 June 1493, surgeon Hans Seyff amputated the leg at Linz Castle. Frederick initially recovered well, but he died in August at the age of 77. Contemporaries blamed his death on complications from the amputation, old age, or diarrhea brought on by eating melons. His bowels were probably buried separately, while his amputated leg was interred with him.
4. Frederick, Emperor of Germany and King of Prussia (1831–1888)
The most recent Emperor Frederick, born into the royal House of Hohenzollern, had distinguished himself as a soldier during the wars leading up to the establishment of the German Empire in 1871 under his father Emperor William I. As Crown Prince of the new empire, he believed that Germany should evolve toward a more constitutional and parliamentary form of government, which often brought him into conflict with the conservative policies of Chancellor Otto von Bismarck. Historians have often cited his illness as a lost opportunity to change European history.
Frederick had long been a heavy smoker. In January 1887, he developed hoarseness. German physicians suspected a malignant growth of the larynx and recommended a laryngectomy, radical and risky at the time but offering the only real chance of cure. Frederick’s wife, the Crown Princess Victoria (daughter of Queen Victoria), distrusted the German doctors’ grim prognosis and intervened to bring in the celebrated British specialist Dr. Morell Mackenzie. Mackenzie examined tissue samples and disputed the cancer diagnosis, declaring the growth potentially benign. This gave the royal family hope and provided justification to reject surgery. This disagreement erupted into a fierce Anglo-German medical and political dispute. The German doctors were highly confident in their cancer diagnosis, but the pathologist Rudolf Virchow’s initial biopsy results were inconclusive. By late 1887, it was too late for curative surgery. Frederick’s condition deteriorated rapidly, and as the cancer progressed and obstructed his airway, he underwent a tracheotomy. He died in June 1888. Later, Mackenzie published a book defending his conduct; the German doctors responded furiously but were essentially correct from the start. The issue was never purely medical. Frederick and Victoria were known liberals who hoped to steer Germany toward a constitutional, parliamentary model; his son, the future Kaiser Wilhelm II, was authoritarian and impatient for power. The controversy remains a classic example of the dangers of allowing political considerations to influence medical judgment.