Great Saxon revolt

The Great Saxon Revolt was a civil war between 1077 and 1088 early in the history of the Holy Roman Empire led by a group of opportunistic German princes who elected as their figurehead the duke of Swabia and anti-king Rudolf of Rheinfeld, a two-way brother-in-law of the young Henry IV, Holy Roman Emperor (Henry was crowned at the age of six and took on his offices when aged sixteen). It followed the Saxon Rebellion of 1073–75.

The duke had played power politics with the young Emperor several years earlier in his reign, and was demonstrably ruthless (kidnapping and forcing the marriage to Henry's sister) even without the support of the other princes of the Kingdom of Germany. The allied nobility were moved to take advantage of the momentary weakness of the Emperor in a period when he was at odds and had been excommunicated by Pope Gregory VII over the issue of who was entitled to appoint whom, who was therefore subservient to whom, as well as a dispute over the Emperor-elect's desire to divorce from his arranged wife.

After meeting with a penitent Henry IV in the fall of 1076, the pope had removed the first excommunication of the impetuous and hot-headed twenty-six-year-old monarch. However, during the same fall-winter season the organizers of the revolt by the nobility were arranging for all to meet in late winter to further their own ends against the interests of the young emperor-elect. With the delays of news and events imposed by High Middle Ages travel, communications heralding the rapprochement were delayed enough that the decision was made to just go ahead and meet anyway. The diverse council of Saxon, Bavarian, and Carinthian princes met in the March 1077, about as soon as early spring travel conditions allowed, in Forchheim (Oberfranken), and despite the reconciliation between the pope and Henry decided to press forward with their desires to expand their own powers.

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