Why Iltutmish was known as the real founder of the delhi sultanate ?

Dear student,

Though Qutub din Aibak established the Mamluk dynasty but Iltutmish is considered as the true founder of Delhi Sultanate.

He was the third ruler of the Slave dynasty but he strongly consolidated his position in the whole country.

He founded the Delhi Sultanate in 1211 and received the Caliph's investiture in his rule. 

He defeated Mahamood Ghazni, Multan rulers, Bengal invaders and firmed his control over his territories.

He crushed revolts, protected and strengthened the boundaries and established a strong and consolidated Sultanate. He sent expeditions against the rebel Rajputs at Gwalior, Ranthambore, Bayana and Jalor. Rajput rulers of Ujjain and Ranthambore were defeated by him. He also recovered Gwalior and Bayana from them. In other words, he completed the tasks of Qutbuddin Aibak and therefore, is regarded as the actual founder of the Slave Dynasty/Delhi Sultanate.

Regards