The treaty of 1769 between Hyder Ali and the English company proved more in the nature of a truce and Hyder Ali accused the company of not observing the terms of the defensive treaty by refusing to help him when the Marathas attacked Mysore in 1771. Haider found the French more helpful than the English. Further in 1778 English in India seized the French settlements including Mahe a port which was very crucial for Haider Ali for the entry of supplies. Haider Ali tried to take Mahe port but in vain. He arranged a joint front with the Nizam and the Marathas against the common enemy -the English East India Company. The war lasted from 1780-1784. But he died in 1782 and was succeeded by his son Tipu Sultan.
Tipu continued the war for another year but absolute success eluded both the sides. Tired of war the two sides concluded peace Treaty of Mangalore. By this Treaty it was decided that English would return Srirangapatnam to Tipu and Tipu would handover Fort of Badnur to English.