The Partition of Bengal took place on October 16, 1905, during the British colonial rule in India. It was carried out by Lord Curzon, who was the Viceroy of India at that time. The partition divided the Bengal Presidency into two separate entities: Bengal and Eastern Bengal and Assam. The primary motive behind the partition was to weaken the growing nationalist movement in Bengal.

However, due to widespread protests and opposition from the Indian National Congress and other nationalist organizations, the partition of Bengal was eventually annulled. The decision to reunite Bengal was announced on December 12, 1911, and took effect on April 1, 1912. Therefore, the partition of Bengal officially ended in 1912.