The circumstances that led to the non-cooperation movement:

1. Rowlatt Act: The Rowlatt Act was passed in 1919 by the British government in India, which gave the colonial authorities extensive powers to arrest and detain Indian nationalists without trial. This act was deeply resented by Indians as it violated their civil liberties.

2. Jallianwala Bagh Massacre: In 1919, the infamous Jallianwala Bagh massacre took place in Amritsar, where British troops under the command of General Dyer fired upon a peaceful gathering of Indians, resulting in the death of hundreds of innocent people. This brutal incident further fueled the anti-British sentiment among Indians.

3. Khilafat Movement: The Khilafat Movement, initiated by the Indian Muslim community, aimed to protect the Ottoman Caliphate, which was under threat from the British. Mahatma Gandhi saw this as an opportunity to unite Hindus and Muslims in the struggle against British imperialism.

4. Discontent among peasants and workers: The economic hardships faced by the Indian peasants and workers, combined with the excessive taxation policies of the British, created a sense of frustration and anger among the masses. This discontent provided a fertile ground for the non-cooperation movement to gain momentum.

Reasons behind Gandhi's decision to withdraw the movement:

1. Chauri Chaura incident: On February 5, 1922, a group of protesters in Chauri Chaura, Uttar Pradesh, set fire to a police station, leading to the death of 22 policemen. Gandhi, who believed in non-violence, was deeply disturbed by this incident as it went against the principles of the movement. He feared that the movement might turn violent and decided to call it off.

2. Increasing acts of violence: Along with the Chauri Chaura incident, there were other instances of violence during the non-cooperation movement. Gandhi was concerned that the movement was losing its non-violent character and that further escalation of violence would harm the overall objective of achieving independence through peaceful means.

3. Reassessing the strength of the movement: Gandhi realized that the non-cooperation movement had not achieved its desired outcomes. The British government had not met the demands of the movement, and the mass participation that Gandhi had anticipated did not materialize. He believed that continuing the movement in its current form would only lead to more disillusionment among the people.

4. Strategic retreat: Gandhi viewed the withdrawal of the non-cooperation movement as a strategic retreat rather than a complete surrender. He wanted to reorganize and strengthen the Indian National Congress, as well as emphasize the importance of non-violence as a means to achieve independence. He believed in the power of satyagraha (non-violent resistance) and wanted to refocus the movement towards constructive work and self-reliance.

In conclusion, the non-cooperation movement was called off by Gandhi due to the Chauri Chaura incident, the increasing violence, the reassessment of the movement's strength, and the strategic need for a retreat. Gandhi's decision reflected his commitment to non-violence and his strategic vision for the larger goal of achieving independence for India.