Sibylle was the eldest child of the Duke
Henry IV of Saxony (1473–1541) from his marriage to
Catherine of Mecklenburg (1487–1561), daughter of the Duke
Magnus II of Mecklenburg. She married on 8 February 1540 in
Dresden Duke
Francis I of Saxe-Lauenburg (1510–1581). This relationship turned out to be important for Sibylle's brother
Maurice during the
Schmalkaldic War. The marriage proved unhappy and Francis accused Sibylle of
vindictive and unloving acts. In later years, Sibylle and Francis reconciled again. In 1552, Sibylle asked her brother
Maurice to financially assist her husband, so he could redeem some goods and villages from
Lübeck. In 1588, the Duchess played a prominent role in the affair of her son Maurice, who lived in Buxtehude in the Abbot's House since 1585/86, with Adam von Tschammer's wife Gisela against whom she initiated a trial of
witchcraft. Sibylle died in 1592 in Buxtehude and was buried in the Cathedral of
Ratzeburg. == Children ==