The struggle for power between Sultan and the Turkish Chiefs “Chahalgani” which began during the reign of Raziya continued.
After Raziya’s death, the power of Chahalgani increased.
Behram Shah (AD 1240–42) and Masud Shah (AD 1242–46) were made Sultans and removed in succession.
After them, in AD 1246, Ulugh Khan (later known as Balban) placed the inexperienced and young Nasiruddin (grandson of Iltutmish) on throne and himself assumed the position of Naib (deputy).
To further strengthen his position, he married his daughter to Nasiruddin.
Sultan Nasiruddin Mahmud died in AD 1265.
According to Ibn Battuta and Isami, Balban poisoned his master Nasiruddin and ascended the throne.