(a) Reasons launching to the Non-cooperation Movement are: 

1. In 1918, those peasants who had been facing the effects of famine and drought resorted to Satyagraha to have their demands fulfilled. In 1918-1919 Ahmedabad mill workers strike also received Gandhi’s support. These movements of local character brought Gandhi closer to the life of the people. He would now think of challenging the total authority of the Government. 

2. The Rowlatt Act was passed in March 1919 to curb the growing nationalist upsurge in the country as this act gave enormous power to the police to search a place and arrest any person they disapproved of without warrant. 

3. During a protest meeting in Amritsar against Rowlatt Act, the military commander of Amritsar, General O’Dyer ordered firing on a peaceful and unarmed gathering in which 1200 people got killed and 300 got injured, which shocked Gandhiji and he decided to stop co-operation with the British Government at all levels. 

(b) Quit India movement. Reasons: 

1. Failure of the Cripps Mission: The failure of the Cripps Mission left no meeting ground between the Congress and the government. It was clear from the proposals that the government was not willing to grant independence in the near future. The Indians were also not happy at the proposals of Cripps Mission because proposals contained within them provisions which could divide India into hundreds of independent provinces. 

2. The communal situation was worsening day-by-day. The Muslim League was demanding a separate state i.e., Pakistan, because all the leaders of the League proclaimed that Muslims could not expect any justice at the hands of the congress. This spoiled the communal situation. 

(c) Impact of the Movement:

1. The movement provided a base to the Congress Gandhi mobilised masses in this movement. All sections of society—peasants, workers, lawyers, students, moneyed classes, women and oppressed people participated in their struggle for freedom. 

2. The movement undermined the power and prestige of the British Government. It created an anti British feeling in the country. 

3. Repression failed to crush the spirit of the people. The movement made the people bold and patriotic. 

4. Gandhi was determined to emancipate the poor and the oppressed. Removal of untouchability and promotion of Khadi became essential tool in Gandhi’s struggle against British rule. Message of Swadeshi was spread. 

5. Another positive achievement was that the movement set the scene of Hindu Muslim unity. Never before any movement received the willing support of Hindus and Muslims alike.