Mas'ud was sultan for 16 years. In 1112, Mas'ūd III built the Palace of Sultan Mas'ud III in Ghazni, Afghanistan. Mas'ūd also built one of the Minarets of Ghazni.[2][3][4] Signs of weakness in the state became apparent when he died in 1115, with internal strife between his sons ending with the ascension of Sultan Bahram Shah as a Seljuk vassal.[5] Bahram Shah defeated his brother Arslan for the throne at the Battle of Ghazni in 1117.