When is International Mother Language Day celebrated?

International observance days such as those proclaimed by UNESCO or the United Nations carry a fixed calendar date tied to a specific historical or thematic reason; once an international body proclaims the date, it is commemorated on that same day every year worldwide.

UNESCO's General Conference proclaimed International Mother Language Day in November 1999 to promote linguistic and cultural diversity and multilingualism. The date chosen, 21st February, commemorates the Bengali Language Movement: on 21st February 1952, students in Dhaka (then East Pakistan, now Bangladesh) were killed while demonstrating for official recognition of the Bengali language. Since 2000, 21st February has been observed globally as International Mother Language Day, and the United Nations General Assembly later welcomed the observance as part of its efforts to promote multilingualism.

• 1st January marks the Gregorian New Year and carries no UNESCO language-related proclamation.

• 14th February is widely observed as Valentine's Day, unconnected to any language-rights observance.

• 13th April falls within the mid-April window of several regional South Asian solar New Year and harvest festivals (such as Vaisakhi), not with any UNESCO-designated language observance.

The United Nations' own official list of international days and weeks corroborates the UNESCO proclamation by listing 21st February as International Mother Language Day.