Bengal was partitioned by the British viceroy Lord Curzon.
Lord Curzon partitioned Bengal on 20th July 1905.
The partition came into effect on 16th October 1905.
At that time of partition, Bengal was the biggest province of British India that included Bihar and parts of Orissa.
The British argued that the division was for administrative convenience.
The partition of the Bengal is an example of the British policy of divide and rule.
The main reason for the partition of Bengal was to destroy the political influence of the educated middle class among whom the Bengali intelligentsia was the most prominent.
The swadeshi movement was started to protest against the partition of Bengal.
Bengal partition was finally cancelled by Lord Hardinge in 1911.