In The History of My Going for Refuge, Sangharakshita writes that

“‘A Bird’s-eye View of Indian Buddhism’, as I called it at one stage, was a lengthy article produced on the eve of my departure from India in 1964.... It had been commissioned by the Syndics of the Oxford University Press for the second edition of The Legacy of India, but having heard nothing from them for a long time and having assumed (wrongly, as it turned out) that they had decided not to use the article, in 1980 I included it in the fifth edition of A Survey of Buddhism as the Introduction to that work.”

– The History of My Going for Refuge, Complete Works, vol. 2, p. 452.