Question

how did the company get hold of the Diwani rights of Bihar Bengal and Orissa in detail​

Answer 1

Grant of the Diwani of Bengal, Bihar and Orissa to the East India Company by the Great Mughal Shah Alam (1765) Introduction: After Robert Clive had conquered Bengal in 1757, imposing a Nawab (governor) of his choice, the Great Mughal offered him the Diwani (civil administration) of the province.