More than a million of young men left India for fighting the First World War, and for their well being and care in the foreign land, millions of animals like cows, buffalos, horses, donkeys etc were sent along with tons and tons of food related supplies. The First World War had its impact on the entire world. Social systems were affected across world and being actively involved in the war; Indian society was not an exception. Therefore, this paper is about how the immigration of millions of men and the exportation of tons and tons of supplies had impacted caste system in India during the First World War. As primary resources, I have referred to letters of Indian sepoys who fought during the First World War in the various parts of the world. The source of the letters is David Omissi’s book titled Indian Voices of the Great War: Soldiers’ Letters, 1914-1918. It is also important to note here that this paper is a section of a chapter of my M.Phil dissertation submitted to the Centre for English Studies, Jawaharlal Nehru University, New Delhi, India.