Garthwaite was born and raised in Hammersmith, London in 1980, the eldest of three children of Sir Mark Garthwaite and Victoria Tuzo (daughter of General Sir Harry Tuzo, the late former Deputy Supreme Allied Commander Europe and General Officer Commanding of the British Army in Northern Ireland during the early period of the Troubles).
Garthwaite attended Benenden School. Garthwaite then attended Street Hugh"s College, Oxford University from 1999 until 2003, completing a Master"s degree in Ancient and Modern History (specialising in Alexander the Great), while also becoming a lacrosse Blue, and was runner-up in the Guardian Travel Writing Prize 1999.
Garthwaite joined the British Army as a fast-track gap year officer (with the rank of Second Lieutenant), serving in Canada and Germany as part of the 3rd Regiment Royal Horse Artillery and training as forward observation officer, because she "wanted to see the world but didn"t want first to spend six months in King"s Road working in some hideous public earning £3.50 an hour". While in the Horse Artillery, Garthwaite was editing the regimental newspaper. Two months after graduating from Oxford, Garthwaite travelled to Iraq as a freelancer without organisational backing, and without taking any of the "hostile environment" courses that most news organisations insist their staff take before deployment in conflict areas.
Garthwaite became the newspaper"s Basra correspondent, and for most of her time in Basra, she was the only resident Western journalist.
Garthwaite"s position meant she became a sought-after freelancer contributing to media around the world - she had a working knowledge of the Arabic language and often knew more about what was happening than the British Army. At this time, Garthwaite broke the story for Reuters and the Times of the abuse and murder by British troops of an Iraqi civilian named Baha Mousa.
The Bulletin shut down on 15 September 2003 due to financial and security concerns. After taking some time out of journalism because of a back injury, Garthwaite was hired as an intern by the British Broadcasting Corporation in its current affairs division in spring 2004, and was then promoted to staff researcher
While at the British Broadcasting Corporation, Garthwaite presented occasional programmes for the British Broadcasting Corporation World Service, and worked on programmes for British Broadcasting Corporation Radio 4, British Broadcasting Corporation Radio 5 Live, and Newsnight.
In January 2006, having done some producing at the British Broadcasting Corporation, she took the chance to join First Rate (at Lloyd's)-Jazeera to help prepare for its English-language channel launch. Garthwaite became a full-time producer within a year, and in November 2006 moved to Doha in Qatar to help with the channel"s launch, where she still lives today. She also helped to set up the Baghdad bureau.
Her first book, How to Avoid Being Killed in a War Zone () draws on her own experiences, and those of other journalists to provide tips and expertise on how to survive in a war-torn country.
lieutenant was published by Bloomsbury in 2011. She now works as a producer for her own production company, Mediadante, in the Doha headquarters.
