Events

• The city of Oslo is founded by Harald Hardråde of Norway.

Births

• May 18 - Omar Khayyam, Persian poet, astronomer, mathematician and philosopher (d. 1123)
• Alexius I Comnenus, Byzantine emperor (d. 1118)

Deaths

• August 9 - Pope Damasus II
• December 13 - Al-Biruni, Persian mathematician (b. 973)