(a) Reasons Leading 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) Two reasons behind the launching of Quit India Movement are: 

1. India was not willing to take part in the Second World War but was forced to join without any consent. Due to this the economy of the country worsened and the expenditure went up three folds. Due to this congress decided to start Quit India Movement. 

2. On the night of 9th August the British Government arrested many eminent leaders like Gandhiji, Moulana Azad, Sardar Patel, Jawaharlal Nehru and other members, of working committee and sent them to Pune. This hasty action of the Government lead to start the movement without any effort. 

(c) Impact of the Non-cooperation movement on the National Movement: 

1. The National Movement truly became a mass movement. 

2. It brought forward Hindu-Muslim unity as Khilafat leaders actively supported the Non-cooperation movement. 

3. The Demand for Swaraj became much more popular. 

4. The movement provide a great national base to the congress.