Nasiruddin was the son of Shahzada Nasiruddin, son of Iltutmish who died in 1229, while Iltutmish was still alive. Iltutmish was devastated by death of his son. Due to this he developed close relationship with Nasiruddin, son of Shahzada. He made special arrangements for his grandson and wanted everyone to recognise nasiruddin as his son for political reasons.
In 1246, Nasiruddin was seventeen years old and governor of Baraich. After the murder of Masud Shah, the conspirator rushed nasiruddin to Delhi disguised as women along with his mother.
Balban was one of the benefactor of nasiruddin, though he was not involved in murder of Masudshah. Balban was also father in law of Masudshah.
Nasiruddin was pragmatic person and knew the reality of being an Sultan of Delhi.
Last three sultan were murdered by Turkish nobles. So, he approached the role of sultan cautiously. He took no part in running the government and left all administrative decision to his Turkish noble. Balban was his Wazir(prime minister) and exercised real power on his behalf of sultan. Nasiruddin was more a figure head than actual ruler of his empire.
Nasiruddin was very religious person and pious person. He had four wife and no concubine. He left nobles to settle all matters between themselves and did not interfere in their feud. Soon became acceptable to all nobles. Had nasiruddin decided to interfere in feud in support of one faction he would have been killed by other faction. So, he kept himself completely aloof from politics and never took any step without the permission of ruling elite. He also married daughter of balban in 1249 to cement his position as sultan. He kept himself busy with religious activities like writing copy of Quran.
Removal of Balban
In 1253, Nasiruddin, after being provoked by dissatisfied nobles, removed balban as a Wazir and asked him to assume governorship of one of the province. Balban immediately complied with the request. Dissatisfied nobles were betting that balban will revolt but he didn’t. Within a year Sultanate engulfed in political chaos. Sultan realised his mistake and reappointed balban as Wazir. Nasiruddin kept balban as his Wazir till his own death in 1266.