Like many of his planter colleagues, Walter joined the Malayan Volunteer Forces, specifically the Perak Battalion of the 1st Federated Malaya States Volunteer Force (1FMSVF), to undertake semi-regular army training.
The Volunteer Forces, which originated in 1854 at the time of the Crimean War, were similar in concept to the British Territorial Army and comprised personnel from:
- all branches of the Malayan Government Service
- the Mines and Plantations,
- business communities,
- the Medical Profession and;
- the Church.
Whatever their background, they were motivated by a profound sense of wanting to do everything in their power to defend the Crown Colony of Malaya and her dependents.
The men remained in their civilian employment and received military training at night and on weekends.