Tughril Beg

Orphaned early and raised, by tradition, in the household of his grandfather Seljuk, Tughril Beg turned a migrating clan into an empire. With his brother Chaghri he led the Seljuk Turkmen across the Oxus into Khorasan in the 1030s, where they shifted from raiding to conquest. In 1038 Tughril was proclaimed ruler in Nishapur, and in 1040 the brothers met Sultan Mas'ud of Ghazna at Dandanaqan, near Merv. The Ghaznavid army, exhausted by chasing an enemy that refused pitched battle, was destroyed, and Khorasan passed to the Seljuks in a single afternoon.

The brothers then divided their inheritance by temperament as much as geography. Chaghri took the east and ruled from Merv; Tughril took the west and kept moving. Through the 1040s and early 1050s he subdued Rayy, Hamadan, and Isfahan, absorbing the fractured Buyid emirates of Persia while Turkmen bands ranged ahead of him into Azerbaijan and the Byzantine borderlands. He governed less as a steppe khan than as a Persian monarch in the making, retaining local bureaucracies and presenting himself as the armed champion of Sunni orthodoxy.

That presentation reached its logical end in December 1055, when Tughril entered Baghdad. The Shia Buyids, who had dominated the Abbasid caliphs for a century, were swept aside, and Caliph al-Qa'im formally invested Tughril as sultan, delegating to him the temporal authority of Islam. The arrangement was tested almost immediately: the Turkish general al-Basasiri, backed by the Fatimids of Cairo, seized Baghdad in 1058 and drove the caliph from his palace. Tughril crushed the rebellion, restored al-Qa'im in 1060, and fixed the pattern of caliph and sultan that would govern Sunni political theory for two centuries.

In 1062 he pressed the caliph into granting him a daughter in marriage, an unprecedented honor for a Turkish warlord, but the union was brief. Tughril died at Rayy in September 1063, around seventy-three years old and childless. The throne passed to his nephew Alp Arslan, son of Chaghri, and through that line the dynasty endured. Tughril's achievement was the empire's frame: others would win its famous battles, but he had built the institution of the Seljuk sultanate itself.