21 February (8 Falgun in the Bengali calendar) was International Mother Language Day (Martyrs' Day) since 2000. 21 February was proclaimed the International Mother Language Day by UNESCO on 17 November 1999. Its ceremony was also formally recognized by the United Nations General Assembly in its resolution establishing 2008 as the International Year of Languages.
International Mother Language Day originated as the international recognition of Language Movement Day, which has been commemorated in Bangladesh (formerly East Pakistan) since 1952, when a number of Dhaka university students were killed by the Pakistani police and army in Dhaka during the Bengali Language Movement. International Mother Language Day is observed yearly by UNESCO member states and at its headquarters to promote linguistic and cultural diversity and multilingualism.
On 21 March 1948, Mohammed Ali Jinnah, the Governor General of Pakistan, declared that Urdu would be the only official language for both West and East Pakistan. The people of East Pakistan (now Bangladesh), whose main language is Bengali, started to protest against this. On 21 February 1952, (8 Falgun 1359 in the Bengali calendar), students in the present day capital city of Dhaka called for a provincial strike. The government invoked a limited curfew to prevent this and the protests were tamed down so as to not break the curfew. The Pakistani police fired on the students despite these peaceful protests and a number of students were killed.
