He was born on 13 April 1871 to Alfred Bailey, a barrister and legal scholar, and his wife Fanny Margaret, née Coles, a merchant's daughter.
Cyril attended St Paul's School in London, before studying classics at Balliol College, Oxford (1890–94); he won the Craven and Hertford scholarships.
[1] He epitomised a type of scholar, "of first-rate ability and international reputation who preferred not to seek promotion, titles, or even relief from the duties of teaching, and who were content with the position of tutor at an Oxford college, lavishing much of their time and energy on their pupils.
[1] Alongside receiving five honorary doctorates, Bailey gave the Sather Lectures at the University of California in 1932 and was elected a fellow of the British Academy the next year.
He died on 5 December 1957 and was survived by his wife, Gemma (daughter of the historian and bishop Mandell Creighton), who had attended the University of Oxford herself, and produced a history of Lady Margaret Hall in 1923.