Delhi Sultanate is one of earliest eras of monarchy,as Delhi-based kingdoms. It is a term used to cover 5 short dynasties-Mamluk,Kalji,Tughlaq,Sayyid and Lodi.
Qutubddin Aibak is the founder of the Delhi Sultanate.
The Delhi Sultanate was not a very successful empire. The Khilji dynasty was able to conquer central India,but unfortunately couldn't unite the entire Indian subcontinent. Due to the repeated attacks of Mongols,the empire weakened.Finally, in the first Battle of Panipat(1526), Babur defeated Ibrahim Lodi, the last ruler of the Delhi Sultanate and the glorious Mughal period started.