Why did the Buddha renounce the world?

Popular versions of the reasons why the Buddha renounced the world to seek enlightenment hover around the story that the prince Siddhartha Gautam was pained to see the suffering of a sick, a dead and an old man while on a tour. Dr Ambedkar, in his own interpretation of the Buddha’s story and the Dhamma (The Buddha and His Dhamma), provides an altogether different version. 

According to Ambedkar, Siddhartha had opposed the declaration of war by the Sakya Sangh on the neighbouring Koliyas. Since his was a minority view, he had to bow to the majority and had to take recourse to one of the options left with him.

Siddharth realised the consequences that would follow if he continued his opposition to the Sangh in its plan of war against the Koliyas. He had three alternatives to considerto join the forces and participate in the war ; to consent to being hanged or exiled ; and to allow the members of his family to be condemned to a social boycott and confiscation of property. (page 49) 

Siddhartha opted for the second option and went into exile. His subsequent conversation with his wife Yashodhara reveal that his renunciation had her support.

In the Introduction to the work Ambedkar gives a pointer to his the re-telling of this story.