Duke of Luxembourg-Piney

Duc de Piney (Duke of Piney) was a title in the Peerage of France. The holders were also sometimes called duc de Luxembourg, after the House of Luxembourg, from whom they were descended.

The duchy-peerage was created in 1581 for François de Luxembourg, third son of Antoine de Luxembourg, Count of Ligny and Brienne. He died in 1613 and was succeeded by his son:

Henri de Luxembourg (1583–1616), second duke, was father of Marguerite-Charlotte de Luxembourg (1607–1680), heiress to the title. She married firstly, Léon d'Albert de Luynes (1582–1630), who became third duc de Piney jure uxoris; he was the younger brother of Charles d'Albert, duc de Luynes. Their son, Henri-Léon d'Albert de Luxembourg (1630–1697), fourth duke, resigned the peerage in 1661. His mother simultaneously resigned it to her daughter by her second marriage (the fourth duke's half-sister), Madeleine-Charlotte de Clermont de Luxembourg (1635–1701). She was the daughter of Charles-Henri de Clermont-Tonnerre (died 1674).

Madeleine-Charlotte was married in 1661 to François-Henri de Montmorency (1628–1695), comte de Bouteville and sovereign Count of Luxe; he became fifth duc de Piney jure uxoris and later a Marshal of France. He sued the other peers of France to obtain the precedence of the original Piney peerage created in 1581, by which he would have outranked most of France's dukes.

Their son Charles-François de Montmorency-Luxembourg (1662–1726), sixth duc de Piney-Luxembourg, had previously been created duc de Beaufort, later de Montmorency. He pursued his father's lawsuit claiming precedence based on the princely origin of his ancestors as well as the seniority of his title. But a 1711 edict assigned the Piney dukedom precedence only as of 1661.

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