Complex sentence: Sir Hugh O'Donnell (Irish: "Aodh mac Maghnusa Ó Domhnaill") (died c.1600), was "The O'Donnell" and king of Tyrconnell in medieval Ireland.
Split into simpler sentences: Sir Hugh O'Donnell (Irish: "Aodh mac Maghnusa Ó Domhnaill") (died c.1600), was an Irish Gaelic lord. He was "The O'Donnell" of his clan, and king of Tyrconnell in medieval Ireland.