al-Biruni

Abu al-Rayhan Muhammad ibn Ahmad al-Biruni (born 362 AH / 973 CE in Kath, in the Central Asian region of Khwarazm; died c. 440 AH / 1048 CE in Ghazna, in present-day Afghanistan) was one of the great scholars of the medieval Islamic world. Working chiefly in Arabic, he wrote across astronomy, mathematics, geography, chronology, mineralogy, and the comparative study of religions and cultures. (His death year is usually given as 440 AH/1048, though some scholars argue he lived until about 442 AH/1050 on the evidence of a work he wrote after stating he was over eighty.)

His life tracked the turbulent politics of his region. After his birthplace fell under new rulers, he spent years moving among courts — at Rayy, at Gurgan (Jurjan) under the Ziyarid ruler Qabus ibn Wushmgir, and back in his Khwarazmian homeland — before the conqueror Mahmud of Ghazna annexed Khwarazm in 1017 and brought him to the Ghaznavid capital at Ghazna, his base for the rest of his life.

Accompanying Ghaznavid campaigns into northwest India, al-Biruni learned Sanskrit and studied Indian sciences and beliefs first-hand, producing his celebrated account known as the Kitab al-Hind ("Book of India"), notable for trying to describe another civilization on its own terms. He is also reported to have exchanged sometimes-sharp scientific correspondence with the philosopher Ibn Sina (Avicenna).

His own sectarian affiliation is debated: he identified simply as a Muslim, and modern scholars disagree over whether his background was Sunni or Shia — the site presents this as an open question rather than a settled fact.