Keene was born at the East India College, Haileybury. Henry George Keene (1781–1864) was his father. He was educated at Rugby School and Wadham College, Oxford, going to India as an East India Company employee in 1847. His career as an official was limited, but he began to write. From 1847 to 1882 Keene served in the Bengal Civil Service. During the Indian Rebellion of 1857 he was Superintendent at Dehradun. In his subsequent service, Keene was in frequent disagreement with his superiors, and when he reached the 35 years limit he had not got beyond the grade of a district and sessions Judge. He retired with the decoration of CIE, and with a literary reputation. Keene died on 26 March 1915 at his residence in Westward Ho. The Mughal Empire at its peak extended over nearly all of the Indian subcontinent and parts of Afghanistan.