Peter FitzSimons grew up on a farm in Peats Ridge, New South Wales, the youngest of a large family of siblings. He played rugby union in Australia, Italy and France and represented Australia at international level with the Wallabies. Following his rugby career FitzSimons took up work as a sports journalist in the 1980s and went on to become a full-time columnist with the Sydney Morning Herald.
FitzSimons has written biographies of well known Australians, including sports and political personalities, and narrative non-fiction on Australian history including Batavia (2011) and Australian military campaigns including Kokoda (2004) and Tobruk (2006). Kokoda: Teen Edition was published in 2016.