Alexander Windsor, Earl of Ulster

Alexander Patrick Gregers Richard Windsor was born prematurely on 24 October 1974 at St Mary's Hospital, London.^[3][4][5] He is the only son of Prince Richard, Duke of Gloucester, and Birgitte, Duchess of Gloucester.^[6] As of September 2025^[update], he is 33rd in the line of succession to the British throne.^[7]

Alexander attended Eton College and later graduated with a degree in war studies from King's College London in 1996. He subsequently trained at the Royal Military Academy Sandhurst.^[8]

Alexander was commissioned in the King's Royal Hussars on 10 April 1998 as a subaltern (second lieutenant) with seniority from 14 April 1995; he was given the service number 548299. He was promoted to lieutenant on 10 April 1998 with seniority from 14 April 1997,^[9] and to the rank of captain on 16 October 2000.^[10] He saw active service in Northern Ireland, Kosovo and Iraq.^[8] On 14 January 2003, he transferred from a Short Service Commission to an Intermediate Regular Commission.^[11] On 28 April 2008, he was appointed to the Reserve of Officers, signalling his retirement from the British Army with the rank of acting major.^[12]

Since leaving the army, he has worked in non-governmental organisation roles and is a director of the Transnational Crisis Project.^[13]

On 22 June 2002, Alexander married Claire Booth, a physician, at the Queen's Chapel, St James's Palace.^[14] Lady Ulster is a professor of Gene Therapy and Paediatric Immunology at University College London's Great Ormond Street Institute of Child Health.^[15] The couple have two children:

• Xan Richard Anders Windsor, Lord Culloden (born 12 March 2007)^[16][17]
• Lady Cosima Rose Alexandra Windsor (born 20 May 2010)^[18]

Alexander continues to make public appearances at state events alongside other members of the extended royal family, including the 2022 state funeral of Queen Elizabeth II and the 2023 coronation of King Charles III and Queen Camilla.^[19][20]