Translated and annotated by orientalist Edward Sachau (1845–1930), this 1887–8 two-volume work is the account by Muslim polymath and traveller Alberuni (973–1048) of Indian political and social life in the medieval period. Sachau published the manuscript in Arabic in 1885–6, at the same time working on an English translation. Alberuni, born in Chorasmia, south of the Aral Sea, was one of the leading scholars of his day. He accompanied the Afghan ruler Mahmud on his invasion of India in the early eleventh century, and remained there for thirteen years, making a detailed study of Indian life and culture, and in particular studying the Hindu religion. Alberuni claims that his work is not polemical in nature, but a simple historical record of facts, and he commends the learning of the Hindus in philosophy, mathematics and astronomy. Volume 1 discusses Hindu beliefs, the caste system and the calendar.