In the early hours of March 26, 1971, the undisputed leader of Bengali, Sheikh Mujibur Rahman, declared independence before being arrested by the Pakistani army.

[5] The British introduced the Morley-Minto Reforms in 1909 which made the electorate system based on religion and East Bengal was largely Muslim.

Members of the organisations from Bengal Provincial Muslim League following the ideals of Netaji Subhas Chandra Bose [citation needed] were close to Sheikh Mujibur Rahman.

This organization based in Dhaka wanted to engage in armed struggle with the help of Great Britain under the leadership of Sheikh Mujibur Rahman.

[5] Krishak Sramik Party demanded autonomy for East Bengal in 1953 and won the provincial election against the Pakistan Muslim League in 1954.

[5] Chief Minister A. K. Fazlul Huq and party general secretary Sheikh Mujibur Rahman were placed under house arrest on charges of separatism.

[5] After Ayub Khan imposed military rule in Pakistan in 1958, some members of Awami League formed a separatist organization called "East Bengal Liberation Front" in Jamalpur, they asked Indian prime minister Jawaharlal Nehru for help in the war of independence, but he refused because of the Nehru–Liaquat Pact.

[8] In 1963, Sheikh Mujibur Rahman wrote to prime minister Nehru to discuss the declaration of independence of East Pakistan and the formation of a government-in-exile in London.

[5] Sheikh Mujibur Rahman, now leader of the Awami League, was arrested in 1966 and charged in the Agartala conspiracy case, which accused prominent East Pakistanis of trying to separate the country with help from India, in 1968.

[5] In a party meeting on 5 December 1969, Sheikh Mujibur Rahman proposed to name East Pakistan "Bangladesh" if it became independent.

[5] On 10 March 1970, Sheikh Mujibur Rahman demanded autonomy for East Pakistan based on the Six Point program of the Awami League.

[5] Moulana Abdul Hamid Khan Bhashani ends a public event with the slogan East Pakistan Zindabad on 23 November.

[5] Despite the overwhelming victory, the Awami League was not allowed to form a government by the military administration of Pakistan led by General Yahya Khan.

[5] On 7 March 1971, Sheikh Mujibur Rahman gave a historic speech to resist the West Pakistan administration, through refusing to follow their orders and paying taxes.

[5] On 24 March, soldiers of East Pakistan Rifles raised the flag of independent Bangladesh in Jessore District.

[5] On 27 March, Major Ziaur Rahman, officer of the East Bengal Regiment, declared the Independence of Bangladesh from Swadhin Bangla Betar Kendra on behalf of Sheikh Mujibur Rahman and called the actions of Pakistan Army a massacre while asking for intervention of the United Nations.

[18] The first Independence Day was celebrated on 26 March 1972, in which President Sheikh Mujibur Rahman addressed the nation through a broadcast of the government reforms planned, such as the improvement in social rights.

[19] The launch of Operation Searchlight and declaration of Independence marked the start of Bangladesh Liberation War on 26 March 1971.

The Pakistan Educational Conference of November 1947 proposed Urdu as the national language even though it was spoken by only 3% of Pakistanis, compared to 56% who spoke Bengali.

The Bangla Academy was an institution established in the 1950s as a result of the language movement; after independence, it became a major publisher of textbooks, dictionaries, folk literature, etc.