The area which is now Bangladesh has a rich historical and cultural past, the product of the repeated influx of varied peoples, bringing with them the Dravidian, Indo-Aryan, Mongol-Mughul, Arab, Persian, Turkic, and European cultures. About 1200 A.D., Muslim invaders under Sufi influence, supplanted Hindu and Buddhist dynasties, and converted most of the population of the eastern areas of Bengal to Islam. Since then, Islam has played a crucial role in the region's history and politics. In the 16th century, Bengal was absorbed into the Mughul Empire.
Portuguese traders and missionaries reached Bengal in the latter part of the 15th century. They were followed by representatives of the Dutch, the French, and the British East India Companies. During the 18th and 19th centuries, especially after the defeat of the French in 1757, the British gradually extended their commercial contacts and administrative control beyond Calcutta into the remainder of Bengal and northwesterly up the Ganges River valley. In 1859, the British Crown replaced the East India Company, extending British dominion from Bengal in the east to the Indus River in the west.
In the late 19th and early 20th centuries, Muslim and Hindu leaders began to press for a greater degree of independence. At the movement's forefront was the largely Hindu Indian National Congress. Growing concern about Hindu domination of the movement led Muslim leaders to form the All-India Muslim League in 1906. In 1913, the League formally adopted the same goal as the Indian National Congress: self-government for India within the British Empire. The Congress and the League were unable, however, to agree on a formula to ensure the protection of Muslim religious, economic, and political rights. Over the next 2 decades, mounting tension between Hindus and Muslims led to a series of bitter intercommunal conflicts.
The idea of a separate Muslim state emerged in the 1930s. It gained popularity among Indian Muslims after 1936, when the Muslim League suffered a decisive electoral defeat in the first elections under the 1935 constitution. On March 23, 1940, Muhammad Ali Jinnah, leader of the Muslim League, publicly endorsed the "Pakistan Resolution" that called for the creation of an independent state in regions where Muslims were a majority.
At the end of World War II, the United Kingdom, under considerable international pressure to reduce the size of its overseas empire, moved with increasing urgency to grant India independence. The Congress Party and the Muslim League could not, however, agree on the terms for drafting a constitution or establishing an interim government. In June 1947, the UK declared it would grant full dominion status to two successor states--India and Pakistan. Pakistan would consist of the contiguous Muslim-majority districts of western British India, plus parts of Bengal. The various princely states could freely join either India or Pakistan. These arrangements resulted in a bifurcated Muslim nation separated by more than 1,600 kilometers (1,000 mi.) of Indian territory. West Pakistan comprised four provinces and the capital, Lahore. East Pakistan was formed of a single province. Each province had a legislature. The capital of federal Pakistan was at Islamabad.
Pakistan's history for the next 26 years was marked by political instability and economic difficulties. Dominion status was rejected in 1956 in favor of an "Islamic Republic within the Commonwealth." Attempts at civilian political rule failed, and the government imposed martial law between 1958 and 1962 and 1969 and 1972. The government was dominated by Military and Oligarchies all rooted in the West. Significant amount of national revenues went towards developing the West at the expense of the East. The people of the Eastern wing began to feel increasingly dominated and exploited by the West. Frictions between West and East Pakistan culminated in a 1971 army crackdown against the East Pakistan dissident movement led by Bangabandhu Sheikh Mujibur Rahman, whose Awami League (AL) Party had won 167 seats out of 313 National Assembly seats on a platform of greater autonomy for the eastern province.
Bangabandhu Mujibur Rahman was arrested and his party banned. Many of his aides and more than 10 million Bengali refugees fled to India, where they established a provisional government. India and Pakistan went to war in late November 1971. The combined Indian-Bengali forces soon overwhelmed Pakistan's army contingent in the East. By the time Pakistan's forces surrendered on December 16, 1971, India had taken numerous prisoners and gained control of a large area of East Pakistan, which is now Bangladesh.