Henry IV (; 11 November 1050 – 7 August 1106) was Holy Roman Emperor (1084–1105), King of Germany (1054–1105), and King of Italy and Burgundy (1056–1105). A Salian ruler, he was the son of Henry III and Agnes of Poitou. After his father's death in 1056, his mother acted as regent, granting lands to secure aristocratic support. Unable to control papal elections, she witnessed the growing assertion of the "liberty of the Church", a principle central to the emerging Gregorian Reform. In 1062, Archbishop Anno II of Cologne kidnapped Henry and governed until he came of age in 1065.

Seeking to recover royal estates lost during his minority, Henry relied on lower-ranking officials, provoking unrest in Saxony and Thuringia. He suppressed revolts there in 1069 and 1071, but his promotion of commoners alienated the nobility. Insisting on his royal prerogative to appoint bishops and abbots, he became embroiled in what would later be known as the Investiture Controversy, leading Pope Alexander II to excommunicate Henry's advisers in 1073. After crushing a renewed rebellion in Saxony in 1075, Henry adopted an active policy in Italy, alarming Alexander's successor, Gregory VII, who threatened him with excommunication for selling church offices.

In 1076, German bishops, encouraged by Henry, declared Gregory's election invalid. Gregory responded by excommunicating Henry and releasing his subjects from allegiance. Facing opposition at home, Henry sought absolution through his penitential "Walk to Canossa" in 1077. Though restored to communion, he confronted a rival king, Rudolf of Rheinfelden. Renewed excommunication in 1080 led Henry's supporters to elect the antipope Clement III. Rudolf's death strengthened Henry's position, although his opponents chose a new antiking, Hermann of Salm; in 1084, Clement crowned Henry emperor in Rome.

From 1089 to 1096, Henry campaigned in Italy against his son Conrad II, Matilda of Tuscany, and Welf I of Bavaria. After Clement's death, Henry refrained from supporting further antipopes and proclaimed the first (imperial peace), extending across the whole of Germany, in 1103. In 1105, his younger son, Henry V, forced his abdication. Attempting to regain power, he fell ill and died in 1106 without absolution. His central role in the Investiture Controversy and the "Walk to Canossa" ensured a profoundly contested legacy.

Background

Henry was the third ruler of the Salian dynasty, which governed Germany from 1024 to 1125 and exercised authority over Italy and Burgundy. With a strong claim to the title of Holy Roman Emperor, the German kings regarded themselves as the supreme leaders of Christendom and as entitled to influence papal elections in Rome. However, Roman aristocratic factions dominated the papacy, and their rivalries culminated in the schism of 1045 with three rival popes. To resolve the crisis, Henry's father, Emperor Henry III, convened the Synod of Sutri in 1046, which deposed the claimants and installed the German bishop Suidger of Bamberg as Pope Clement II.

By virtue of his anointing with holy oil, Henry III conceived kingship as a priestly office. He regarded himself as "Vicar of Christ", entitled to govern Church and state alike. After receiving the hereditary title of patrician from the Romans, he held the right to cast the first vote at papal elections, thereby securing the appointment of German reform-minded popes. The third of these, Leo IX, prohibited the sale of church offices and promoted clerical celibacy. Yet imperial control over the Church conflicted with the reformist ideal of "liberty of the Church", a tension that culminated under Henry IV in the Investiture Controversy.

Germany, Italy, and Burgundy consisted of semi-autonomous provinces governed by bishops, abbots, and dukes. Although kings sought to control these offices, they ultimately depended on the cooperation of the leading aristocracy. Towards the end of his reign, Henry III came into conflict with several powerful dukes. He alienated Duke Bernard II of Saxony by supporting his rival, Archbishop Adalbert of Hamburg, and Godfrey the Bearded, Duke of Upper Lotharingia, married the wealthy Beatrice of Tuscany without imperial consent. The frequent royal presence in the royal domains in Saxony further increased local resentment, which later erupted into revolts under Henry IV.

Beyond the empire, Henry compelled Duke Bretislav I of Bohemia and King Peter of Hungary to swear fealty, but lost influence in Hungary after Peter's deposition in 1046. Dynastic conflicts there prompted further German interventions. In 1047, Henry asserted authority over the Norman princes of southern Italy, but increasingly relied on the papacy to represent imperial interests.

Early life

Born on 11 November 1050, Henry was the son of Emperor Henry III by his second wife, Agnes of Poitou. Henry was most likely born in his father's palace at Goslar. Henry III had fathered four daughters, but his subjects were convinced only a male heir could secure peace. Henry was first named for his grandfather, Emperor Conrad II, but his godfather, Abbot Hugh of Cluny, convinced the Emperor to give his name to his heir. While celebrating Christmas 1050 at Pöhlde in Saxony, Henry III designated his infant son as his successor.

Archbishop Hermann baptised Henry in Cologne on Easter Sunday 1051. In November, the Emperor held an assembly at Tribur. The German princes who attended the meeting elected the one-year-old king. They stipulated they would acknowledge him as his father's successor only if he ruled justly during his father's lifetime. Historian Ian S. Robinson supposes the princes actually wanted to persuade Henry III to change his methods of government since the child king had no role in state administration. At Christmas 1052, the Emperor made Henry the duke of Bavaria.

Archbishop Hermann crowned Henry King of Germany in Aachen on 17 July 1054. On this occasion, the Emperor probably granted Bavaria to Henry's two-year-old younger brother, Conrad. When Conrad died in 1055, the Emperor gave Bavaria to Empress Agnes. He betrothed Henry to Bertha of Savoy in late 1055. Her parents, Adelaide, Margravine of Turin, and Otto, Count of Savoy, controlled north-western Italy.

Henry III fell seriously ill in late September 1056. Already dying, he commended his son to the protection of Pope Victor II, who had come from Italy to Germany to seek the Emperor's protection against the Normans of southern Italy. Henry III died on 5 October 1056.

King under guardianship

Agnes's regency

At the age of six, Henry became sole ruler of the empire and was crowned at Aachen with papal support, while his mother Agnes served as regent and guardian. She supervised his education with the royal (unfree liegeman), Cuno. Agnes secured aristocratic loyalty through grants, reconciled with Godfrey the Bearded, and appointed Conrad of the Ezzonid family, an opponent of her late husband, as Duke of Carinthia. She paid little attention to Burgundy and Italy, entrusting Burgundy to the aristocrat Rudolf of Rheinfelden after appointing him Duke of Swabia.

In Saxony, Otto of Nordmark, a former exile, attempted a coup against royal authority; the loyalist Bruno II of Brunswick killed Otto but was himself mortally wounded. Henry retained his father's Roman title of patrician, but in Rome the principle of the "liberty of the Church" became increasingly dominant, and Godfrey the Bearded's brother was elected Pope Stephen IX without royal intervention. After Godfrey seized Spoleto and Fermo in Italy, rumours of his imperial ambitions with papal support spread, but Stephen IX died unexpectedly on 29 March 1058.

The Roman aristocracy installed Giovanni, Cardinal-Bishop of Velletri, as pope without consulting the German court. His election was contested, and the cardinals supported Bishop Gerard of Florence. After consulting the princes, Henry designated Gerard as pope in June 1058. Later that year he concluded an agreement with King Andrew I of Hungary. It secured the succession of Andrew's five-year-old son Solomon over Béla, Andrew's brother, and arranged Solomon's betrothal to Henry's sister Judith. Gerard was installed as Pope Nicholas II in December 1058. He and Godfrey the Bearded expelled Giovanni of Velletri from Rome. Advised by the monk Hildebrand, Nicholas issued the decree , granting the cardinals the right to elect popes while confirming unspecified imperial prerogatives. At the same time, reformers such as Cardinal Humbert of Silva Candida challenged the rulers' right to invest bishops and abbots.

Pope Nicholas invested two Norman rulers, Robert Guiscard and Richard I of Capua, with southern Italian duchies in 1059. In return, the Normans swore fealty to Nicholas and promised to support him against his enemies. Although the duchies were imperial fiefs, Nicholas's action did not necessarily trespass on imperial rights, because the popes had acted as the emperors' representatives in southern Italy for a decade. However, the Pope's treaty with the Normans forged their lasting alliance.

In 1060, after Agnes's uncoordinated intervention failed, Béla of Hungary overthrew his brother Andrew with Polish support. Andrew soon died of his wounds, and his family fled to Germany. The German frontier duchies were then reinforced: Agnes granted Bavaria to the Saxon Otto of Nordheim and replaced Duke Conrad of Carinthia with Berthold of Zähringen in early 1061.

Relations with the papacy deteriorated for unknown reasons, and after Nicholas II's death the reformers elected his successor, Alexander II, without royal consent on 30 September 1061, although Roman aristocrats had dispatched an embassy to Henry asking him to name his candidate. In response Henry convened a synod at Basel, which elected Cadalus, Bishop of Parma, as Antipope Honorius II on 28 October. The papal schism divided the German clergy: some prelates, such as Archbishop Adalbert of Hamburg, supported Honorius II, while others, including Archbishop Anno II of Cologne, recognised Alexander II.

Coup of Kaiserswerth and Anno's rule

Agnes's support for Honorius, the failure of the Hungarian campaign, and her favoritism for Bishop Henry II of Augsburg had undermined her authority. In April 1062, Archbishop Anno and other nobles, including Otto of Nordheim and Egbert I of Brunswick, removed her from the regency in the Coup of Kaiserswerth. During the coup Anno lured Henry onto a ship on the Rhine and had it cast off. Fearing for his life, Henry leapt into the river but Egbert rescued him from drowning.

Agnes then withdrew from government, and Anno assumed control, also taking charge of Henry's education. He sought to end the schism and sent his nephew Burchard II, Bishop of Halberstadt, to start negotiations with Pope Alexander. Reformist clerics such as Peter Damian defended Alexander's election and questioned imperial prerogatives in papal elections, arguing that Henry's "right to participate in the papal elections … is subject each time to reconfirmation by the pope". Respect for royal authority also declined in Germany, and armed conflict erupted between the retainers of Abbot Widerad of Fulda and Bishop Hezilo of Hildesheim in Henry's presence at Goslar in June 1063.

In 1063 Henry led a campaign in Hungary to restore Solomon against his uncle Béla I, gaining his first military experience. After Béla died in an accident, the German army entered Székesfehérvár, where Henry installed Solomon as king and attended his marriage to Judith. Archbishop Adalbert of Hamburg accompanied Henry during the campaign and emerged as his "protector" in royal diplomas, indicating his growing influence, especially after Archbishop Anno left for Italy in 1064 to recognise Pope Alexander.

Reign as king

First years of majority