Simon Mauchline was born in Darwin, Northern Territory, Australia on May 29, 1980. He moved to Brisbane, Queensland in 1985, where he attended school until his graduation in 1997. While studying Nursing at the QLD University Technology, Simon worked with people with a disability. He graduated in 2010, then started a graduate nurse position at the Royal Brisbane Emergency Trauma Centre, where he worked full-time until 2014 and then part-time and/or on a casual basis until the present.

In 2014, Mauchline began working in a ‘fly-in fly-out’ Remote Area Nurse position in several remote indigenous communities in far north Queensland and Torres Strait Islands. Starting in 2017, Simon worked for Christian US NGO north of Erbil in a Kurdish-run refugee camp which hosted predominantly ex-Mosul residents. He also worked for a German-based NGO for several weeks in West Iraq, mainly treating people affected by trauma and helping establish a destroyed Emergency Room.

In 2018, while on mission to Raqqa, in northeast Syria, to help set up and man a destroyed medical facility, Simon was seized and detained by the Assad Regime alongside colleague Martin Lautwein in Qamishli. He was taken to Damascus and detained for 48 days in Military Intelligence Branch 235 (also known as Palestine Branch) under the pretense of spying for Israel/US. Mauchline and Lautwein were then released after intervention from the Czech Republic in August 2018.

Since returning to Australia in August 2018, Simon has worked as a nurse on the Covid frontline in Brisbane until late 2021, when he started a position as a health teacher aide position at a local primary school.