In the early 1900s, millions of people peacefully started to protest against British control. One of the people who led the freedom movement was Mahatma Gandhi, who only used peaceful tactics, including a way called "ahimsa", which means "non-violence". On 15 August 1947, India peacefully became free and independent from the British Empire. India's constitution was founded on 26 January 1950. Every year, on this day, Indians celebrate Republic Day. The first official leader (Prime Minister) of India was Jawaharlal Nehru.