1. British wanted to control the rich province of Bengal .
2. alwardi khan , the nawab of Bengal , was an able administrator . he had followed a policy of keeping the British merchant under control . but after his death , his grand son , siraj-ud-dualah became the nawab .
3. the British started extending the fortification of Calcutta .
4. siraj-ud-dualah's troops took over Calcutta .
5. Robert Clive set out from madras with an army of 900 Europeans and 1200 sepoys, armed, trained in the European style of warfare and recaptured Calcutta .
6. the British consolidated their position in Bengal by making Mir jafar , a commander of Bengal army, as the nawab of Bengal
7. Mir jafar couldn't fulfill the constant demands of the British.
8.they installed his son in law , Mir qasim as the nawab. he granted equal trade facilities to the British and Indian merchants.
9. this annoyed the British and they attacked him.
10.Mir qasim took refuge at awadh with shiya-ud-dualah where mughal emperor, shah Alam , was also taking refuge .