Why Did Gandhi Start the Non-Cooperation Movement?

Following World War I, Indians expected political concessions for their support of the British war effort. Instead, the British passed the draconian Rowlatt Act in 1919. This act gave the British government enormous powers to repress political activities, allowing them to arrest and imprison Indian political activists without a trial for up to two years. The slogan against this act was 'No Dalil, No Vakil, No Appeal'. Gandhi's outrage over this unjust law was the primary catalyst for organizing a nationwide Satyagraha.

On April 13, 1919, a peaceful gathering in Jallianwala Bagh (Amritsar) to protest the Rowlatt Act turned into a bloodbath when General Dyer ordered his troops to open fire on the unarmed crowd. Hundreds of innocent men, women, and children were killed. The sheer brutality of the massacre, and the subsequent failure of the British government to adequately punish Dyer (the Hunter Commission), completely shattered Gandhi's faith in the British sense of justice.

After World War I, the Ottoman Empire was defeated, and there were rumors that a harsh peace treaty would be imposed on the Ottoman Emperor (the Khalifa or Caliph), who was considered the spiritual leader of Muslims worldwide. Indian Muslims launched the Khilafat Movement to protest this. Gandhi saw this as a golden opportunity to unite Hindus and Muslims under a single national umbrella against the British. He combined the Khilafat demands with the demand for 'Swaraj' (self-rule), birthing the Non-Cooperation Movement.

Gandhi urged Indians to surrender British titles and honors, boycott government schools and colleges, boycott law courts, refuse to serve in the British army, and boycott foreign goods (encouraging the use of Khadi instead). The movement saw unprecedented mass participation.