Henry Nixon was born in the 1970s at St Margaret's Hospital on Crown Street in the inner-Sydney suburb of Surry Hills. As a teenager, he attended Narrabundah College in Canberra, and there he studied drama.

He graduated from the Australian National University with an Arts degree, majoring in Anthropology, Sociology and English, before deciding to pursue an acting career. He auditioned for and was accepted into the National Institute of Dramatic Art (NIDA) in Sydney.

Since graduating from NIDA in 2000 Nixon has worked extensively in film, television and theatre.

In 2002 he regularly played the character Chris King in the popular Channel 5 TV serial Don't Blame Me (or Don't Blame the Koalas). He is known for his work as Sterlo McCormack on All Saints, an Australian hospital drama. In 2009, Nixon portrayed Lieutenant Hugh (Ivy League) Corrigan in the HBO Film follow-up to Band of Brothers, The Pacific.