Viscount Avonmore is a title in the Peerage of Ireland created on 29 December 1800 for the former Attorney-General for Ireland and Lord Chief Baron of the Exchequer for Ireland, Barry Yelverton, 1st Baron Yelverton. He had been created Baron Yelverton on 15 June 1795. The 4th Viscount fought numerous legal battles to prove that his first purported marriage to Theresa Longworth was illegal. Since the death of the 6th Viscount in 1910, both titles have been dormant. According to Cracroft's Peerage, heirs-male may exist in Australia[1]