State of Bahawalpur was a state in the Punjab region of South Asia that existed as a sovereign polity from 1748 to 1833 and as a princely state, under subsidiary alliance with British India from 1833 to 1947 and later Dominion of Pakistan from 1947 to 1955. It was a part of the Punjab States Agency; and covered an area of with a population of 1,341,209 in 1941. The capital of the state was the town of Bahawalpur.
The state was founded in 1748 by Nawab Bahawal Khan Abbasi. On 22 February 1833, Abbasi III entered into a subsidiary alliance with the British, by which Bahawalpur was admitted as a princely state. When British rule ended in 1947 and British Raj was partitioned into India and Pakistan, Bahawalpur joined the Dominion of Pakistan. Bahawalpur remained an autonomous entity until 14 October 1955, when it was merged with the province of West Pakistan.
thumb|Painting of the Darbar of the Nawab of Bahawalpur State, circa first half of the 19th century
As part of the 1809 Treaty of Amritsar, Ranjit Singh was confined to the right bank of the Sutlej. The first treaty with Bahawalpur was negotiated in 1833, the year after the treaty with Ranjit Singh for regulating traffic on the Indus. It secured the independence of the Nawab within his own territories and opened up the traffic on the Indus and Sutlej. The political relations of Bahawalpur with the British Raj were regulated by a treaty made in October 1838, when arrangements were in progress for the restoration of Shah Shuja to the Kabul throne.
During the First Anglo-Afghan War, the Nawab assisted the British with supplies and allowing passage and in 1847-48 he co-operated actively with Sir Herbert Edwardes in the expedition against Multan. For these services, he was rewarded by the grant of the districts of Sabzalkot and Bhung, together with a life-pension of one lakh. On his death, a dispute arose regarding succession. He was succeeded by his third son, whom he had nominated in place of his eldest son. The new ruler was, however, deposed by his elder brother, and obtained asylum in British territory, with a pension from the Bahawalpur revenues; he broke his promise to abandon his claims and was confined in the Lahore Fort, where he died in 1862.
In 1863 and 1866 insurrections broke out against the Nawab who successfully crushed the rebellions; but in March 1866, the Nawab died suddenly, not without suspicion of having been poisoned, and was succeeded by his son, Nawab Sadiq Muhammad Khan IV, a boy of four. After several endeavors to arrange for the administration of the country without active interference on the part of the Government, it was found necessary, on account of disorganization and disaffection, to place the principality in British hands. In 1879, the Nawab was invested with full powers, with the advice and assistance of a council of six members. During the Afghan campaigns (1878–80) the Nawab placed the entire resources of his State at the disposal of the British Indian Government, and a contingent of his troops was employed in keeping open communications, and in guarding the Dera Ghazi Khan frontier. On his death in 1899 he was succeeded by Muhammad Bahawal Khan V, who attained his majority in 1900, and was invested with full powers in 1903. The Nawab of Bahawalpur was entitled to a salute of 17 guns.
Independence of Pakistan
left|[[Noor Mahal palace, constructed in 1872 by Sadeq Mohammad Khan IV|thumb]]
The predominantly Muslim population supported the Muslim League and the Pakistan Movement. After the independence of Pakistan in 1947, the minority Hindus and Sikhs migrated to India while the Muslim refugees from India settled in Bahawalpur state. After the independence of Pakistan, the Nawab of Bahawalpur Sadeq Mohammad Khan V proved to be very helpful and generous to the government of Pakistan. He gave seventy million rupees to the government and the salaries of all the government departments for a couple of months were also drawn from the treasury of Bahawalpur state. He donated his private property to the University of the Punjab, King Edward Medical College and the Mosque of Aitchison College, Lahore. At the time of independence, all the princely states of British India were given a choice to join either Pakistan or India and have no option to remain independent, outside both. On 5 October 1947 the Nawab signed an agreement with the government of Pakistan according to which Bahawalpur State acceded to Pakistan, and the accession was accepted on 9 October. Thus the State of Bahawalpur was the first state to accede to Pakistan.