The international chess federation, FIDE (= Fédération International des Échecs), was established in 1924 on the 20th of July, which date thus became that of “International Chess Day”, as FIDE terms it.

95 years, 4 months and 19 days later, on 12th December 2019, the General Assembly of United Nations (a younger organisation dating back to 1945) similarly proclaimed 20th of July to be “World Chess Day”. The main significance of this may be that chess has in a way been recognised by the UN as something akin to, if not actually a form of, “sport”, though of course nobody defines “sport” before arguing for or against whether chess should be recognised as a “sport”.

Both FIDE and the UN have webpages devoted to this anniversary:

https://www.fide.com/news/630,

https://www.un.org/en/observances/world-chess-day,

as does the ECF:

https://www.englishchess.org.uk/world-chess-day/

The theme FIDE has identified for this year’s anniversary is “to make an appeal to the members of our chess community and ask you to teach someone how to play chess to mark this day.” That, of course, is not easily done in the present circumstances, so maybe forging a way through to resurrecting over-the-board chess might be more pragmatic, and there are those actively engaged in attempting to do this.

Of necessity, such celebratory events as are outlined on the above webpages are being held on line, and so are not everyone’s cup of tea.