Brabazon Ponsonby, 1st Earl of Bessborough

Brabazon Ponsonby, 1st Earl of Bessborough (1679 – 4 July 1758) was a British politician and peer. He was the son of William Ponsonby, 1st Viscount Duncannon, and Mary Moore. He was an active politician from 1705 to 1757 in Great Britain and Ireland. He represented Newtownards and Kildare County in the Irish House of Commons. He inherited his father's viscountcy in 1724 and was made Earl of Bessborough in the Peerage of Ireland in 1739. He is buried in Fiddown, County Kilkenny, Ireland.

Ponsonby married Sarah Margetson, an heiress whose family owned Bishopscourt, County Kildare, and his family remained there until the 1830s.

• Member of Parliament for Newtownards, County Down, between 1705 and 1714
• Captain, 27th Regiment; Enniskillen – 1707
• Sheriff and Governor of County Kilkenny – 1713
• Sheriff and Governor of County Kildare – 1714
• Member of Parliament: Kildare – 1715 to 1724
• Privy Counsellor (invested) – 10 May 1727
• Commissioner of the Revenue – 1739 to 1744
• Marshal of the Admiralty in Ireland – 1751 to 1752
• Lord Justice in Ireland – 1754 to 1755
• Vice-Admiral of Munster – 1755
• Lord Justice in Ireland – 1756 to 1757

Ponsonby married twice:

• Elizabeth Sankey: (circa 1680 – 17 July 1738), daughter of John Sankey and Eleanor Morgan, on 28 November 1733.

• Sarah Margetson (d. 21 May 1773), daughter of John Margetson and Alice Caulfeild, in 1704. Sarah was married before to Hugh Colvill. Sarah's children by Brabazon Ponsonby:

• 2nd Viscount Duncannon, of the Fort of Duncannon, county of Wexford (succeeded) – 17 November 1724
• 2nd Baron Bessborough, of Bessborough, county ofKilkenny (succeeded) – 17 November 1724
• 1st Earl of Bessborough, Ireland (created) – 6 October 1739
• 1st Baron Ponsonby of Sysonby, county of Leicester, Great Britain (created) – 12 June 1749