By J. L. Berggren

The Central Asian scholar Abu al-Rayhan al-Biruni was born in Khwarizm on 4 September, 973. During his youth at least four powers were contending with each other in and around Khwarizm, so that in his early twenties al-Biruni spent much of his time either in hiding or fleeing one king to seek the hospitality from another. Despite these setbacks, however, he completed eight works before the age of 30, including his Chronology of Ancient Nations, the sort of work necessary to any astronomer who wanted to use (say) ancient eclipse records and needed to convert the dates given in terms of some exotic calendar into dates in the Muslim calendar.

Excerpted fromĀ Episodes in the Mathematics of Medieval Islam (2nd Edition)