Martyn graduated from the University of Liverpool in 2004 with a BA in Ancient History and Archaeology, and was awarded an MA in Contemporary History and Politics by Birkbeck College, University of London, in 2011. He has held senior roles in several charities and not-for-profit organisations, including serving as Executive Director of the UK-St Helena Heritage Trust from 2022 – 2025. In addition to his work for the BIAA, Martyn is a martial arts instructor, a consultant, and Honorary Treasurer of the British Association for Near Eastern Archaeology (BANEA). In August 2025, Martyn was elected as a Fellow of the Society of Antiquaries of London.