Why did industrial production in India increase during the First World War?

Why did industrial production in India increase during the First World War?
or
Explain the impact of the First World War on industrial production in India.
Ans. Till the First World War, industrial growth was slow.
The war created a dramatically new situation with British mills busy with war production to meet the needs of the army. Manchester imports into India declined. Suddenly, Indian mills had a vast home market to supply.
As the war prolonged, Indian factories were called upon to supply war needs, jute bags, cloth for army uniforms, tents and leather boots, horse and mule siddles and a host of their items.