The First Deccan War was a military conflict fought from 1847 - 1849 between the forces of the Bengal Sultanate and Jaunpur Sultanate against the forces of the Deccan Sultanate.
Years before the war, the Jaunpur Sultanate and Bengal Sultanate had reconciled with one another and established close relations. Generally seeking to re-establish dominance and control over India, Bengal sought to conquer Deccan which was seen as the core and heart of India. In this, they were aided by the Jaunpur Sultanate who jointly invaded Deccan in 1847 with Bengal. The war itself had not been anticipated by any leader in India, and this granted Bengal the element of surprise which allowed them to completely destroy the Deccan navy in the Battle of Shahipur. The war ended within two years when Bengal and Jaunpur were able to push deep into Deccan territory and capture strategic positions in the Deccan Sultanate. It was regarded as a significant victory and lauded as the revival of Bengal. For the Deccan Sultanate, it was a humiliating victory and exposed their weakness.
The territorial gains acquired by Jaunpur and Bengal in the war generally led to heightened tensions between Deccan and the former two, given that the occupied land was of industrial and agricultural importance to Deccan. Occasional skirmishes would increase and would later on result in the Second Deccan War .