Henry was the last undisputed claimant to the lordship of the Fews. Some O'Neill families today claim descent from this Henry O'Neill, but contemporary documentation show that he died without leaving any descendants. Following Henry's death, Felix O'Neill (c1720-1792) was identified by contemporaries as the "person to whom the Lordship of the Fews in the North of Ireland in right and justice belongeth". Indeed, Felix was considered to have a valid claim to be the Chief of the entire O'Neill clan. In his book "History of Ireland" (1758–62) Abbé James MacGeoghegan of the Irish College in Paris wrote of the house of the O'Neills that "the present representative is Felix O'Neill, the chief of the house of the Fews, and an officer of rank in the service of his Catholic Majesty". Felix O'Neill was born in Creggan in County Armagh. He descended from Aodh Buidhe O'Neill, brother of Sir Henry O'Neill. Felix left Ireland for a career in the Spanish Army and is well remembered for his rescue of Charles Edward Stuart ("Bonnie Prince Charlie") following the Battle of Culloden. Felix became a lieutenant general in the Spanish Army and his four sons in turn all had honourable careers in the Spanish military. While most of them did not marry and have families, the youngest son Juan O'Neill (1768-1809) married Vincenta Gual y Vives de Cananas from Palma, Mallorca, and took up residence on the island. Having attained the rank of Captain-General, he died aged 40 leaving a son Felix who was only a year old. Through this man the O'Neills of the Fews line continued in Mallorca in the 19th century and in Argentina in the 20th century. The current day Argentinean descendants of Lieutenant General Felix O'Neill therefore have an historical claim to be leaders of this branch of the O'Neill dynasty. In the 2000s, Dr. Tulio José O'Neille of Buenos Aires in Argentina has come to light as the genealogically senior living heir of the O'Neill of the Fews. His grandfather moved from Spain and he is descended from Lt. Gen Felix O'Neille (1 November 1720 — 12 July 1792), from the Creggan, who serve in the Spanish Army, serving at times at Captain General of Aragon and Galicia. A contrary claim to the leadership of the dynasty comes from Spanish nobleman Don Carlos O'Neill, 12th Marquis de la Granja, who has been described as "the Prince