Background
Éléonore d'Esmier d'Olbreuse was born at the Château d'Olbreuse in Deux-Sèvres near Niort, France into a Huguenot family of lower nobility.
Éléonore d'Esmier d'Olbreuse was born at the Château d'Olbreuse in Deux-Sèvres near Niort, France into a Huguenot family of lower nobility.
She was Countess of Wilhelmsburg from 1674 and Duchess of Brunswick-Lüneburg from 1676. She was also the great-grandmother of Frederick the Great. Her parents were Alexandre d'Esmier d'Olbreuse and Jacquette Poussard du Bas-Vandré et de Saint-Marc.
She went to the royal court in Paris as a lady-in-waiting in the service of Marie de la Tour d'Auvergne, Duchess of Thouars, whose son had married Emily of Hesse-Kassel, daughter of William V, Landgrave of Hesse-Kassel, in 1648. There the beautiful Éléonore met the unmarried George William, Duke of Brunswick-Lüneburg, who immediately fell in love with her. Éléonore became his mistress and received the title Lady of Harburg.
In 1674 the child was legitimised and Éléonore became the Duchess of Wilhelmsburg. Two years later the couple could finally marry. It was a happy marriage.
Their daughter was married in 1682 to George Louis, the son of her father's brother, Ernest Augustus, Elector of Hanover, for dynastical reasons. The marriage was a disaster. Éléonore d'Esmier d'Olbreuse died on 5 February 1722, nearly blind, in Celle Castle, Celle.
She mentioned 342 persons in her will. She was buried in the Stadtkirche St. Marien (town church of St Mary) in Celle.
