John Maxwell was the son of Arthur Henry and Vereana Estelle Beresford Maxwell, of Corduff, Co. Dublin, Irish Republic.

He was a member of the recently formed Royal Marine Detachment 385.  He landed by canoe from HMS THRASHER on 9 March 1945 as part of Operation Copyright, a reconnaissance of beaches and airfields on Phuket Island, Thailand.

After a number of failed attempts to be recovered to the submarine, and various contacts with the Japanese and Thai militia, he was captured on 21 March.  He was subsequently executed by the Japanese on 20 July 1945.

He was initially buried at Johor Bahru in Malaysia but is now interred at Kranji War Cemetery in Singapore.