The Mughal Empire declined rapidly after the death of Aurangazeb. The Mughal court became the scene of factions among the nobles. The weakness of the empire was exposed when Nadir Shah imprisoned the Mughal Emperor and looted Delhi in 1739. The causes for the downfall of the Mughal Empire were varied. To some extent, the religious and Deccan policies of Aurangazeb contributed to its decline. The weak successors and demoralization of the Mughal army also paved the way for it. The vastness of the empire became unwieldy. The financial difficulties due to continuous wars led to the decline. The neglect of the sea power by the Mughals was felt when the Europeans began to settle in India. Further, the invasions of Nadir Shah and Ahmad Shah Abdali weakened the Mughal state. Thus the decline and downfall of the Mughal Empire was due to the combination of political, social and economic factors.
The Deccan policy of the Mughals started from the reign of Akbar, who conquered Khandesh and Berar. Jahangir fought against Malik Amber of Ahmadnagar. During the Shah Jahan's reign, Aurangazeb, as governor of Deccan, followed an aggressive Deccan policy. When he became the Mughal emperor, for the first twenty five years, he concentrated on the northwest frontier. At that time, the Maratha ruler, Sivaji carved out an independent Maratha kingdom in the territories of north and south Konkan.
To contain the spread of the Marathas, Aurangazeb decided to invade Bijapur and Golkonda. He defeated Sikandar Shah of Bijapur and annexed his kingdom. Then, he proceeded against Golkonda and eliminated the Kutb Shahi dynasty. It was also annexed by him. In fact, the destruction of the Deccan kingdoms was a political blunder on the part of Aurangazeb. The barrier between the Mughals and the Marathas was removed and there ensued a direct confrontation between them. Also, his Deccan campaigns exhausted the Mughal treasury. According to J.N. Sarkar, the Deccan ulcer ruined Aurangazeb.
In his private life, Aurangazeb was industrious and disciplined. He was very simple in food and dress. He earned money for his personal expenses by copying Quran and selling those copies. He did not consume wine. He was learned and proficient in Arabic and Persian languages. He was a lover of books. He was devoted to his religion and conducted prayers five times a day. He strictly observed the Ramzan fasting.
In the political field, Aurangazeb committed serious mistakes. He misunderstood the true nature of the Maratha movement and antagonized them. Also, he failed to solve the Maratha problem and left an open sore. His policy towards Shia Deccan Sultanates also proved to be a wrong policy.