The conflict between the empire and the reformed papacy that ran from approximately 1075 to 1250 — usually called, after its most spectacular incident, the Investiture Controversy — was the longest political-constitutional dispute in medieval European history. It began as a quarrel over who appointed bishops and ended as a structural rebalancing of the relationship between secular and ecclesiastical authority across western Christendom. By the time it was over, the empire had lost its Ottonian-Salian capacity to govern through the bishops; the great lay magnates had acquired the autonomous princely jurisdictions that would define the late-medieval imperial constitution; the papacy had emerged as a sovereign monarchical institution of European reach; and the empire's centre of operational gravity had shifted decisively from the north German plains to the Staufer territories of Swabia and Italy.
Gregory VII and Henry IV
The figure who initiated the controversy was Pope Gregory VII — the Tuscan monk Hildebrand, elected pope in 1073 — a former adviser to four predecessors and the principal architect of the eleventh-century reform programme that had aimed, since the 1050s, to free the Church from lay control. The 1059 decree of Pope Nicholas II had already removed the appointment of the pope from the German emperor's hands by establishing the College of Cardinals as the electoral body. Gregory extended the principle to the appointment of bishops generally: in his Dictatus Papae of 1075 (an internal memorandum that was probably never publicly promulgated, but whose principles he in fact applied), he asserted that the pope alone might depose emperors, that no episcopal appointment was valid without papal confirmation, and that lay investiture — the practice of secular rulers appointing bishops by handing them the staff and ring of office — was simoniacal and void.
Henry IV — by 1075 a twenty-five-year-old emperor in personal majority — refused to accept this. The collision came over the archbishopric of Milan, where Henry installed his preferred candidate in defiance of Gregory's instructions. Gregory excommunicated Henry on the 22nd of February 1076. The excommunication was a more serious matter than later periods have appreciated: the German princes, several of whom had been waiting for an opportunity to reduce royal authority, used the excommunication to suspend their obligations to Henry and to summon a diet at Tribur in October 1076 that effectively demanded the king's reconciliation with the pope or his deposition. Henry, his political position collapsing, made the famous journey to Canossa in January 1077 — three days standing barefoot in the snow at the gate of Countess Matilda's castle in Emilia — to receive absolution from Gregory. The reconciliation was politically useful in the short term and a disaster in the medium term: the German princes had learned that they could discipline an emperor by means of papal excommunication, and they would use the lesson repeatedly across the next two centuries.
The controversy was nominally settled by the Concordat of Worms of 1122, under Henry V and Pope Calixtus II, which separated the spiritual investiture of bishops (with the staff and ring, reserved to the pope) from the temporal investiture (with the sceptre, reserved to the emperor). In substance the concordat was a compromise that gave both sides part of what they had wanted. In structural terms, the imperial-church system did not recover: bishops henceforth identified primarily with the papacy in religious matters and increasingly accumulated independent secular jurisdictions of their own, becoming the prince-bishops of the late-medieval empire rather than the imperial agents of the Ottonian period.
The Staufer dynasty
The Staufer (or Hohenstaufen) dynasty held the imperial title from 1138 to 1250, with one short interruption (the Welf emperor Otto IV, 1209–1218). The four major Staufer emperors — Conrad III, Frederick I Barbarossa, Henry VI, and Frederick II — represent the medieval empire at its high-political ambition. Frederick Barbarossa (1152–1190) was the figure who attempted to revive Ottonian-style imperial authority through a series of Italian campaigns (six in total) aimed at restoring imperial sovereignty over the Lombard cities. The campaigns produced the great battles of the period — Legnano in 1176, the Lombard League's defeat of imperial forces — and the diplomatic settlement of the Peace of Constance (1183), which conceded substantive municipal autonomy to the Italian communes in exchange for nominal imperial overlordship. Barbarossa is also the emperor who, in 1157, formally added the adjective "Holy" (sacrum) to the imperial title — a deliberate counter-claim against the papacy's monopoly on sacrality. The "Holy Roman Empire" as a phrase begins here.
Barbarossa drowned on the 10th of June 1190 in the Saleph river in Cilicia while leading the German contingent of the Third Crusade. (He had been preceded on Crusade by Conrad III in 1147 and would be followed by Henry VI's planned but uncompleted Crusade of 1197.) The medieval German tradition that Barbarossa was sleeping in a cave at the Kyffhäuser, waiting to return at Germany's hour of need, dates from his death — a folkloric persistence of imperial-restoration hopes that nineteenth-century Romantic nationalism would later harvest. Barbarossa's grandson Frederick II (1212–1250) was the most cosmopolitan of the medieval emperors — raised in Norman Sicily, fluent in Greek, Arabic, Latin and several vernaculars, ruler simultaneously of Germany, Italy, Burgundy and Sicily, the patron of the first vernacular Italian literary court — and the most heavily excommunicated. His running conflict with the popes (Gregory IX excommunicated him three times, Innocent IV declared him deposed at the Council of Lyon in 1245) consumed most of his reign. He died at Castel Fiorentino in Apulia in December 1250.
The Crusades
The empire's involvement in the Crusades requires a brief survey. The First Crusade (1096–1099), which captured Jerusalem, was led predominantly by French and Norman nobility; the imperial contribution was small (Godfrey of Bouillon was duke of Lower Lorraine, technically an imperial vassal, but the leadership of the crusade was not imperial). The Second Crusade (1147–1149), in which Conrad III participated personally, produced no territorial gains and severely embarrassed both Conrad and the French king Louis VII. The Third Crusade (1189–1192) was the largest German military mobilisation of the period; Barbarossa's army of perhaps 100,000 (numbers contested) crossed Hungary and the Balkans before Barbarossa's death dissolved the expedition. The Fourth Crusade (1202–1204) — which sacked Constantinople rather than reaching the Holy Land — involved no significant German participation; the Fifth (1217–1221) and Sixth (1228–1229) were partially German-led; the Sixth, conducted by Frederick II while excommunicated, achieved the diplomatic recovery of Jerusalem from al-Kamil of Egypt without fighting. The Crusades did not produce lasting territorial acquisitions for the empire and did not significantly alter its institutional development; they did, however, consume substantial fiscal resources and political attention.
The death of Frederick II
Frederick II's death in 1250 effectively ended the Staufer dynasty. His son Conrad IV died in 1254; his grandson Conradin, the last Staufer claimant, was captured by Charles of Anjou after the Battle of Tagliacozzo in 1268 and executed at sixteen in the Naples marketplace. The imperial title became a contested prize among rival claimants for the next twenty-three years — the period known as the Great Interregnum (1254–1273), during which no universally recognised emperor reigned and during which the great princely territories acquired the institutional autonomy that would define the post-1273 empire. The election of Rudolf I of Habsburg in 1273 restored the imperial title and inaugurated the dynastic period that, with brief interruptions, would last until the empire's dissolution in 1806. But the institution that Rudolf inherited was not Otto's or Barbarossa's. It was a confederation of effectively sovereign principalities ruled by a primus inter pares emperor whose powers were constrained by election capitulations, by the imperial diet, and by the seven (later eight, later nine) prince-electors. The next chapter follows this constitutional consolidation.
End of Chapter II