Subsidiary alliance was a system used by Wellesley to bring Indian states within the orbit of British power.Under his subsidiary alliance system,the ruler of the allying Indian state was compelled to accept the permanent stationing of a British force within his territory.Under this system those who entered into alliance with British were not allowed to have their own army rather were have to be protected by British army,also the ruler's in alliances were not allowed to enter into alliance with other power's nor they were allowed to wag a war with other power's without the permission of British.Many regions like Hyderabad in 1799,Mysore in 1799 came into subsidiary alliance.