The Saxon revolt refers to the struggle between the Salian dynasty ruling the Holy Roman Empire and the rebel Saxons during the reign of Henry IV. The conflict reached its climax in the period from summer 1073 until the end of 1075, in a rebellion that involved several clashes of arms.
Name
The Saxon Rebellion or Rebellion of the Saxons () is also commonly called the Saxon Uprising (not to be confused with the Saxon Wars, also called the Saxon Uprising).
Origins
Undercurrents of discord between the Salian royal family and the Saxons already existed under Henry's father, Emperor Henry III. This may have been primarily due to his Rhenish Franconian origin as well as his numerous stays in the Imperial Palace of Goslar, which were associated with a disproportionately high economic burden on the surrounding population. With the accession of Henry IV in 1065 this conflict intensified, as Henry made demands on numerous Imperial domains (Reichsgüter) in the centre of the Saxon heartland around the Harz mountains—especially the silver mines of Rammelsberg. To secure these estates he initiated a castle building programme, erecting numerous fortresses along the range, the most prominent being the Harzburg castle. This was perceived as a threat by the Saxons. In addition, these castles were staffed with ministeriales of Swabian origin, who frequently plundered the Saxon population to make up for their lack of income.
In 1070 the Saxon count Otto of Nordheim, Duke of Bavaria since 1061, had been accused by the ministerialis Egeno I of Konradsburg of planning an assault on the king's life. Even though Otto was deposed and banned, he nevertheless gained the support of the son of Ordulf, Duke of Saxony, the young Magnus. During this time, King Henry IV had been both captured and arrested. While Otto was pardoned, Magnus remained in custody at the Harzburg and was not released even after his father's death in 1072, as he showed no intention of renouncing the Saxon ducal dignity.
Motives
To grasp the reason for the outbreak of the uprising, it is important to deal with the persons and parties involved: Emperor Henry IV, the Saxon nobility and the remaining imperial princes.
Henry IV
The king had his own rationales, which were also based on the Coup of Kaiserswerth and which had far-reaching consequences. The period after the coup was used by the imperial princes to further extend their power base within the Empire, since there was no overall de facto ruler able to hinder them. Empress Agnes herself was too weak and had fallen into disgrace, and the young king was in the hands of Anno of Cologne. When Henry was dubbed a knight in 1065, he was able to counter these ensuing developments. However, the course of events should not be seen as a recuperation, since the loss of royal lands in the Harz region may be regarded as of low importance and therefore not an essential motive. These areas had already been a bone of contention under Henry III between the Salians and Saxony. The castle building programme should rather be seen as an expression of royal power, because Henry supported himself prominently through the ministeriales, who were dependent on his benevolence in order to free himself from the imperial princes. But this drew further displeasure from the princes.
The Saxon nobility
The motives of the Saxon nobles are now obvious, as they were hugely affected by Henry's actions and were consequently outraged. They did not want to give up so easily the influence that they had built up during the absence of a ruler. This independence, which the king himself tried to achieve, led to a competition with the king, which in turn led to dissatisfaction among the Saxon princes. Henry's endeavours led to the desire for a ruler who was easier to control and to the king being blamed by the Saxons for his abuse of official authority. There was also a conflict due to the so-called "royal immediacy", the regular presence of the king in certain parts of the Empire. This situation was possibly overdramatized; for the king stayed in other parts of the Empire without similar complications. Among the Saxon princes, a certain Otto of Northeim, in particular, found the king a serious thorn in his side due to his participation in the Coup of Kaiserswerth and his expansion of possessions in the Harz. Because of this dispute and the later loss of his estates, Otto takes a leading role in the insurrection during the course of the alleged murder plot against the king.