Governor General Canning was widely criticized in Britain after the Revolt of 1857 due to his policy of clemency towards Indian sepoys. This policy was seen as weak and lenient by many British officials and public, who believed that a more severe punishment should have been meted out to the rebels.

Here is an explanation of why Canning's policy of clemency was criticized:

1. Inadequate response to the revolt: Canning's initial response to the uprising was criticized as being slow and indecisive. Critics argued that he failed to take immediate and strong action to suppress the revolt in its initial phase. This led to the perception that he was not capable of effectively dealing with the situation.

2. Lenient treatment of rebels: Canning's policy of clemency towards the Indian sepoys who participated in the revolt was seen as a sign of weakness. Many British officials and public believed that a more punitive approach should have been taken to deter future rebellions. They saw the rebels as traitors who deserved severe punishment.

3. Lack of retribution: The revolt was a significant challenge to British rule in India, resulting in the loss of lives and property. Critics argued that Canning's policy of clemency failed to provide justice to the victims and their families. They believed that the rebels should have been held accountable for their actions through a more rigorous punishment.

4. Underestimation of the rebellion: Canning's policy of clemency was seen as underestimating the gravity of the rebellion. Many British officials and public believed that the revolt was a serious threat to their rule in India and required a strong response to maintain control. They felt that Canning's leniency would encourage further acts of rebellion.

5. Public backlash: Canning's policy of clemency faced strong opposition from the British public. Newspapers and public opinion in Britain criticized his approach, arguing that it was too lenient towards the rebels. This public backlash added to the criticism faced by Canning.

In conclusion, Governor General Canning was widely criticized in Britain after the Revolt of 1857 due to his policy of clemency towards Indian sepoys. Critics believed that his lenient approach failed to adequately address the rebellion and provide justice to the victims. They argued that a more severe punishment should have been imposed to deter future uprisings.