When the Brits pulled abruptly out of India in 1947, they drew a couple of wiggly lines across the sub-continent to ring-fence the regions where Islam was dominant. That left about 2x7 million people, including Benares silk sari weavers, on the wrong side and up to 1 million dead. Eeee, but they do love a good riot to resolve their differences. The silliness of partitioning the country by the single dimension of Faith, was exposed by delivering the Muslims two lumps of territory separated by 1500km of foreign territory. It was a logistical nightmare; inevitably the state capital was established in West Pakistan because that chunk was larger and Urdu was made the official language in an effort to weld the country into a unitary whole. Although, in terms of population, Bangla speakers in the East slightly out-numbered their co-religionists in the West. The drive to integrate and centralise the country led to East Pakistan being treated increasingly like a bride being dragged unwillingly to the altar of union [note the religious metaphor]. As you know, Bangladesh fought for and obtained independence, with the help of India, in 1971. But the 25 years between 1947 and 1971 were punctuated with numerous incidents and atrocities which only in hindsight look like an independence movement.
On 21st February 1952, students at three of the Third Level Colleges in Dhaka organised a march to protest having to learn Anatomy or Chemical Engineering through Urdu. As college-going people they were smart enough to realise that they'd be better off using English as the medium of instruction if they couldn't have lectures in Bangla. The police reckoned that the march was a riot and fired tear-gas then bullets into the crowd killing a handful of the front-liners and wounding many more. It took two years for the Pakistani parliament to recognise Bangla as an official language of the State. But as with Gladstone and the Home Rule movement in Ireland, it was "too little, too late" and the dead students were transfigured into martyrs.
Starting in year 2000, UNESCO was prevailed upon to a) institute International Mother Language Day and b) pick the debacle of 21/02/52 to celebrate it. Which might not be the most appropriate date to pick to "promote peace and multilingualism", hmmmm? Whatever; I'm all for multi-lingual as an attribute of diversity. We live in interesting times with unprecedented numbers of people migrating unwillingly from their place of birth, many of them heading West towards Ireland, so we'd better start learning some phrases of other languages to understand better these Guests of the Nation. I do wonder about UNESCO, though; it must be really nice to have a job there, shuffling papers and having meetings about Education and Culture from an office in Paris. The relevant sub-committee has decided that the theme for Mother Language Day 2016 is “Quality education, language(s) of instruction and learning outcomes.” WTF! What does that mean? Why "This underlines the importance of mother languages for quality education and linguistic diversity, to take forward the new 2030 Agenda for Sustainable Development", of course. Going forward to clearer communication? I don't think so.