Born a Duchess of Saxe-Lauenburg, she was the wife of Louis William, Margrave of Baden-Baden, a famous Imperial general who was known as the Türkenlouis.

[1] Her older sister Anna Maria Franziska of Saxe-Lauenburg was the future Grand Duchess of Tuscany as the wife of Gian Gastone de' Medici.

Other monarchies also laid claim to the succession, evoking a further conflict involving the neighbouring duchies of Mecklenburg-Schwerin and of Danish Holstein, as well as the five Ascanian-ruled Principalities of Anhalt, the Electorate of Saxony, which had succeeded the Saxe-Wittenbergian Ascanians in 1422, Sweden and Brandenburg.

Their vulnerability as female claimants was taken advantage of by Duke George William of the neighbouring Brunswick-Lunenburgian Principality of Lunenburg-Celle, who invaded Saxe-Lauenburg with his troops, thus inhibiting Anna Maria's ascension as Duchess regnant.

The conflict was finally settled on 9 October 1693 (Hamburger Vergleich), definitively dispossessing Anna Maria and her sister.

Not until 1728, when his son Emperor Charles VI enfeoffed George II Augustus with Saxe-Lauenburg, was the de facto takeover by his grandfather in 1689 and 1693 finally legitimised.

[a] Sibylle was due to marry Prince Eugene of Savoy but preferred the other candidate, the older and impoverished Margrave of Baden-Baden.

Their close relationship is apparent from their correspondence, and from his letters it is obvious that Christian August adored his youngest granddaughter.

The children born to Sibylle were: On the death of Augustus George, the state passed to a distant cousin, Charles Frederick, Grand Duke of Baden and was united with the Margraviate of Baden-Durlach under his rule.

Sibylle has been credited with the reconstruction of Baden-Baden, a state which had been greatly ravaged by the French during their various wars, prior to Louis George's birth.

She held a tight rein on the state's finances and by the time of Louis George's majority in 1727, Baden-Baden was once again flourishing[3] and she had considerably augmented her son's own personal fortune.

During her regency, she helped reconstruct and create many splendid buildings, including palaces, villas and places of worship.

Her mother preferred the French match as it would strengthen ties with a powerful neighbour – one which had ravaged Baden-Baden in the years prior to Johanna's birth.

Having retired, she made pilgrimages and under the influence of the Cardinal Damian Hugo Philipp von Schönborn, she led a very religious life and visited several monasteries.

While living in Ostrov with her husband in the first years of their marriage, the two carried out improvements to the Weißes Schloss [de] ('white castle').