The critical role of Indian Army in World War I is well-known. What’s little known is over 5.5 lakh non-combatants- porters, cooks, sweepers, blacksmiths and others- were an important part of the ecosystem. Historian Radhika Singha of JNU has fleshed out their role in a book, The Coolie’s Great War. She explains her findings to Avijit Ghosh in an email interview.