Grand Duke Jean has served His country as Chief of State for 36 years. Born on 5 January 1921 at Berg Castle and given the name Guillaume Robert Antoine Louis Marie Adolphe Marc d\’Aviano of Luxembourg, He is the eldest son of the Grand Duchess Charlotte of Luxembourg and Prince Felix of Bourbon Parma. He succeeded his mother the Grand Duchess Charlotte on 12 November 1964. On 7 October 2000, Grand Duke Jean abdicated in favor of His eldest son Henri.Guillaume, Hereditary Grand Duke of Luxembourg (Given names: Guillaume Jean Joseph Marie; born 11 November 1981) has been Heir Apparent to the crown of Luxembourg since his father\’s accession in 2000. He is also a descendant of the House of Nassau, founded in 1093, which has ruled Luxembourg since 1890. Guillaume was born in Luxembourg and is the eldest child of Grand Duke Henri of Luxembourg and his wife Grand Duchess Maria Teresa, Cuban-born.