MacMahon family

John MacMahon, an Irish doctor born in Limerick, was naturalised in France in 1749 and married Charlotte Le Belin, Dame d'Eguilly, on 13 April 1750. The same year he was created Marquis d'Eguilly by King Louis XV. His son, the second Marquis, served in the American War of Independence and was a founding member of the Society of the Cincinnati. A grandson of the first Marquis, Patrice de MacMahon, served with distinction as a general in the Crimean War and later in the Austro-Sardinian War, winning the Battle of Magenta on 4 June 1859. The following day he was created Duc de Magenta by the Emperor Napoleon III. The marquesal title held by the senior line of the family was inherited by the younger, ducal line in 1894 and both titles still remain extant.

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