Founder and first supreme leader (Rais Akbar) of Nahdlatul Ulama (NU), Indonesia's largest Islamic organization, established in 1926. Born in Jombang in 1871, he studied for seven years in Mecca under leading Shafi'i and hadith scholars before returning to found Pesantren Tebuireng. Honored as 'Hadratussyaikh' (master of masters), he issued the 1945 Resolusi Jihad that mobilized resistance during the independence struggle. He died on 25 July 1947 and is buried at Tebuireng; his grave is a major pilgrimage site.