In the 18th century, many political reasons led to the decline of the Mughal Empire. Aurangzeb’s campaigns in the Deccan region decreased his military and financial power. His administrative system also started collapsing, as the governors started consolidating power in their own provinces.
Aurangzeb’s successors were unable to keep a check on the mansabdars and the subhedars.
To recover revenues, the governors started increasing the taxes and kept these with themselves. This led to uncontrollable revolts by the peasants and zamindars.
During this time, the empire also faced an attack from Nadir Shah of Iran, in 1739, and Ahmad Shah Abdali of Afghanistan five times - between 1748 and 1761 weakening the empire further.
The nobles divided into those supporting the Iranian and the Turanis nobles.Their power struggle led to the assassination of two Mughal emperors, Farrukh Siyar in 1719 and Alamgir II in 1759, blinding Emperors Ahmad Shah and Shah Alam II as well.
The decline of the Mughal authority led to three types of states in the subcontinent – old Mughal states, independent states under the Mughals, and states which became independent of the Mughal rule.