Henry IV

Henry IV (German: Heinrich 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, coming into conflict with the papacy; Pope Alexander II excommunicated 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 simony.