Mahmud II of Great Seljuk

Mahmud II
Sultan of the Great Seljuq Empire
Reign	1118 -
Predecessor	Muhammad I
Successor	Civil war
Born	c. 1105
Died	1131 (age 26)
Father	Muhammad I

Mahmud II (c. 1105 – 1131) was the Seljuq sultan of Baghdad in 1118 following the death of his father Muhammad I. At the time Mahmud was fourteen, and ruled over Iraq and Persia.

During Mahmud's early reign, his vassal king Garshasp II, who was a favorite of his father Muhammad I, fell into disgrace; slander about him spread to the court that made him lose confidence, and made Mahmud send a military force to Yazd where Garshasp was arrested and jailed in Jibal, while Yazd was granted to the royal cupbearer. Garshasp, however, escaped and returned to Yazd, where he requested protection from Mahmud's rival Ahmad Sanjar (Garshasp's wife was the sister of Ahmad). Garshasp urged Ahmad to invade the domains of Mahmud in Central Persia, and gave him information on how to march to Central Persia, and the ways to combat Mahmud. Ahmad accepted and advanced with an army to the west in 1119, where he together with five kings defeated Mahmud at Saveh. The kings who aided Ahmad during the battle was Garshasp himself, the Emir of Sistan and the Khwarazm-Shah, including two other unnamed kings. After being victorious, Ahmad then restored the domains of Garshasp II.

Ahmad then proceeded as far as Baghdad, whereupon Mahmud was married to one of Sanjar's daughters, made his uncle's heir, and forced to give up strategic territories in northern Persia.

Mahmud's young brother Mas'ud revolted against him in 1120, but the civil war ended the following year due to the intervention of the atabeg of Mosul, Aq Sonqor Bursuqi, and Mas'ud was pardoned. In 1127, he appointed Anushirvan ibn Khalid as his vizier, but removed him from the office one year later. In 1129 Mahmud officially recognized the authority of Zengi, who had supported him against a revolt led by al-Mustarshid, caliph of Baghdad, in Syria and northern Iraq.

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