His first term as the viceroy of the Deccan was between 1713 and 1715.He was given titles of Khan-i-Dauran and later Nizam-ul-Mulk.His second term as the viceroy of Deccan fell between 1720 and 1722.His appointment as wazir of the Mughal empire by Muhammad Shah resulted in his march to the Deccan without waiting for the Emperor’s permission.
He founded the state of Hyderabad as the central Mughal authority was unable to stop him or punish him.He was given viceroyalty of the Deccan and title of Asaf Jah by the emperor though he continued to recognize the emperor as his sovereign.
The reforms introduced by the Nizam include the establishment of peace and security by suppressing all the rebel nobles and maintaining law and order in the region.He made efforts to stop the plundering of the Marathas and revived the agriculture and industry by introducing reforms and incentives.
British started interfering in the affairs of Hyderabad when they started favoring Nasir Jung against Muzaffar Jung. British signed Treaty of Masulipatnam in 1759 with Salabat Jung.
British signed Treaty of Hyderabad in 1766 in which they obtained the five Northern Circars( Ellur,Siccacole,Rajmundry,Mustafanagar and Murtzanagar) from Nizam in return for military assistance. The treaty was renewed in 1768.
Nizam maintained neutrality in the second Mysore wars and cooperated with British in subsequent Mysore wars with British against Tipu Sultan. British under Lord Wellesley signed Subsidiary Alliance with Nizam under which he surrendered all the territories that he got after III and IV Mysore Wars to the British for the maintenance of the subsidiary force in Hyderabad.
In 1853 Nizam was forced by Lord Dalhousie to surrender Berar.Nizam cooperated with British during 1857 first war of independence.