Question

why was the division of bengal withdrawn

Answer 1

because of the widespread protests

Answer 2

The Partition of Bengal was the process of separating eastern parts of Bengal from rest of Bengal. The British Indian government stated the reason of Bengal partition as a measure to improve the administration efficiency. The western region of Bengal comparatively got more focus than that of the eastern region. British projected the partition process would help the administration process by
1) Reducing the burden of government of Bengal and form a separate government for the efficient administration of East Bengal and Assam. 
2) Promoting the development of Assam by including it under the direct jurisdiction of government which was earlier administered by a Chief Commissioner. 
3) Integrating the scattered sections of Orissa under a single administrative umbrella.
The majority of population in the western part of Bengal was Hindu and the eastern part was mainly dominated by Muslim. The Muslims were mostly in favour of the partition whereas the Hindu community opposed the partition of Bengal.

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