The British completed the task of conquering the whole of India from 1818 to 1857 Sindh and the Punjab was conquered and Awadh, the Central Provinces and a large number of other petty states were annexed.
Part of the entire sub-continent was ruled directly by the British and the rest by a host of Indian rulers over whom the British exercised paramount power.
These states had virtually no armed forces of their own, nor did they have any independent foreign relations. They paid heavily for the British forces stationed in their territories to control them. They were autonomous in their internal affairs, but even in this respect they acknowledge British authority wielded through a Resident. They were on perpetual probation. Lord Dalhousie came out to India as the Governor-General in 1848. He was from the beginning determined to extend direct British rule over as large an area as possible.
The chief instrument through which Lord Dalhousie implemented his policy of annexation was the ‘Doctrine of Lapse’. Under this Doctrine, when the ruler of a protected stated died without a natural heir, his state was not to pass to an adopted heir as sanctioned by the age-old tradition of the country.
Instead, it was to be annexed to British India, unless the adoption had been clearly approved earlier by the British authorities. Many states, including Satara in 1848 and Nagpur and Jhansi in 1854, were annexed by applying this doctrine.