Thomas Kingston, the former hostage negotiator and financier who married into the Royal Family

Thomas Kingston, the husband of Lady Gabriella Windsor who died suddenly aged 45, was a financier who married into the Royal Family in a ceremony at Windsor Castle.

Known as Tom, he was a close friend of Pippa Middleton, the Princess of Wales' sister, attending her wedding to James Matthews in May 2017.

Though he worked mostly in finance, he had a stint at the Foreign Office, at one point travelling to Iraq as part of a mission working on the release of hostages.

His death left the Royal Family in mourning.

Lady Gabriella, his wife and Prince and Princess Michael of Kent's daughter, described him as an "exceptional man who lit up the lives of all who knew him".

The King and Queen have sent their "heartfelt thoughts and prayers" to both families.

The wedding

Mr Kingston had been dating Lady Gabriella, known as Ella, for several years when he proposed on the island of Sark in August 2018.

They married at St George's Chapel in Windsor in May 2019, with the late Queen Elizabeth and the Duke of Edinburgh among the guests.

Downton Abbey creator Julian Fellowes was there too.

The reception was at Frogmore House, where Prince Harry and Meghan Markle had their wedding dinner.

His career

Mr Kingston studied at Bristol University, gaining a degree in economic history. He was a chartered financial analyst.

His most recent position was as a director of Devonport Capital, which provides finance to companies operating in "emerging economies".

According to the firm's website, Mr Kingston's first job was with the Foreign Office.

In 2003, he became project manager for a "government-sponsored conflict resolution project in Iraq", it added.

According to The Telegraph, he was a hostage negotiator in Baghdad.

Reverend Canon Andrew White, who spent 10 years running the Anglican church in the Iraqi capital, previously described Mr Kingston as an "exceptional young man", the Daily Mail reported.

In 2006, Mr Kingston joined Schroder's Asset Management in London before moving to Voltan Capital Management in 2012.

His family

Mr Kingston is survived by his parents Mr Martin and Mrs Jill Kingston, and his sisters Mrs Joanna Connolly and Mrs Emma Murray.

Although Lady Gabriella, the King's second cousin, is not a working member of the Royal Family, she and her late husband's relatives are being supported by the Royal Household.

Lady Gabriella is a a writer and contributing editor. She has worked as an arts and travel director for a brand company, and is also a singer-songwriter, having released music for charity.