Every year, 21 February is observed worldwide as the International Mother Language Day to promote awareness of linguistic and cultural diversity, as well as to promote multilingualism. Though proclaimed by UNESCO on 17 November 1999, it was formally recognized by the United Nations General Assembly in a resolution in 2008, establishing it as the International Year of language. The move was initiated by Bangladesh.

21 February has a blood bathed history behind it. Pakistan, the newly formed country in 1947, consisted of two separate wings, East Pakistan, consisting of East Bengal and West Pakistan. However, the two wings were miles apart, separated from each other by India. Despite more than half of the population of the newly formed country belonged to the eastern part, they had a disproportionately small number of seats in the Constituent Assembly, as West Pakistan was politically dominant. In fact, the political leaders of the west wing used to hate, ignore and deprive their eastern counterpart in every respect. In 1948, ignoring the sentiment of the Bengali speaking East Pakistan, the government declared Urdu as the sole national language of the country. The news added fuel to the fire and on 30 January 1952 a strike was observed at Dhaka University.

Next day, representatives of different cultural and political organizations held a meeting chaired by Moulana Bhasani and formed an All-Party Central Language Action Committee, which decided to call a general strike on 21 February 1952 and organized a procession and demonstration. The government of Pakistan immediately imposed Section 144 in the Dhaka City and banned all demonstrations and assemblies. However, the Central Language Action Committee at a meeting on 20 February, decided to violate Section 144 and arrange a meeting at 11.00 am on 21 February on Dhaka University Campus.

Next day, on the history making 21 February of 1952, the Vice-Chancellor of Dhaka University, along with the teachers and thousands of students from school and college of Dhaka, assembled in the University campus. While the Armed police waited outside the gate, the students gathered in groups, started to shout slogans and attempted to break the police cordon. As some people in the crowd started to throw brickbats at the police, the Pakistani police did not miss the opportunity and without trying to pacify or control the gathering, first charged tear gas and then opened fire on the crown, without any warning. Consequently, four students and many other people were killed, along with a nine year old boy named Ohiullah.

That was the beginning of the confrontation between the East and the West wings of Pakistan and the condition of unrest continued as Bengali speakers campaigned for the right to use their mother language. Finally, Pakistan was compelled to accept Bengali as an official language of the country and following the Bangladesh Liberation War in 1971, Bangladesh became an independent country with Bengali as its official language.

Today, 21 February is observed worldwide as the International Mother Language Day. It is also known as ‘Amor Ekushey’ (Immortal 21st) in Bangladesh and is regarded as the root of the Bengali Nationalism and an independent country, Bangladesh. For them, it is a national day with a public holiday to commemorate the sacrifices of the martyrs and commitment to protect Bangla as the national language in 1952.

In Bangladesh, the Shaheed Minar, a national monument at Dhaka University, pays homage to the four demonstrators killed in 1952. The first version of the memorial, built in 1952 was destroyed by the police and the army within a few days, while the second version was destroyed during the Bangladesh Liberation War in 1971. The present memorial, the third version, consists of four standing marble frames, along with a larger double marble frame with a slanted top portion. The four marble frames, symbolizing the four martyrs, stand on a stage, raised about 14 feet (4 m) above the ground and the double frame represents their mothers and the country. Every year on 21 February, people decorate the memorial arena with flowers in memory of the departed souls, who lost their lives on that day.