International Mother Language Day has been observed yearly since February 2000 to promote linguistic and cultural diversity and multilingualism. It commemorates the killing of four students on February 21, 1952, because they campaigned to officially use their mother language, Bengali, in Bangladesh.
Summarized from Wikipedia.
The Linguapax Prize is awarded annually on International Mother Language Day by the Linguapax Institute in Barcelona. The prize recognizes outstanding achievement in the preservation of linguistic diversity, the revitalization of linguistic communities and the promotion of multilingualism. To see the list of awardees, click here.
Canada is home to a large Bangladeshi community. The Bangladesh Heritage and Ethic Society of Alberta offers the annual Ekushey Heritage Award which recognizes people and organizations who are an asset to the local community by awarding a medal of honor for their contributions. The winners are announced on International Mother Language Day.
The 2018 International Mother Language Days theme is Acting Together for Linguistic diversity and Multilingualism.
This poster was downloaded from the UNESCO International Mother Language Day website.