The Bengal Army was the army of the Bengal Presidency, one of the three presidencies of British India within the British Empire.

The Bengal Presidency, officially the Presidency of Fort William in Bengal and later Bengal Province, was a province of British India and the largest of all the three Presidencies. At the height of its territorial jurisdiction, it covered large parts of what is now South Asia and Southeast Asia. Bengal proper covered the ethno-linguistic region of Bengal. Calcutta, the city which grew around Fort William, was the capital of the Bengal Presidency. For many years, the Governor of Bengal was concurrently the Governor-General of India and Calcutta was the capital of India until 1911.