Special days

We all know that Mother's Day is tomorrow.  But I've enjoyed the recent slew of lesser-known holidays.  Here are the ones I'm aware of. 
April 23rd, which is International Book Day, as well as English and Spanish language days
This is due to the fact that Cervantes, Shakespeare, and lesser-known Latin American author Garcilaso de la Vega all died on this date in 1616.  I didn't know that before this year.  My family and I went to a book fair to celebrate.
May 1st, which is International Workers' Day almost everywhere in the world, though in the US we celebrate workers on Labor Day in September.  This disparity is specifically to avoid associating with or validating the socialist and anarchist roots of the May 1st holiday.  Weirdest of all is that May 1st as International Workers' Day has its origin in the US, in Chicago to be exact.  May 1st, 1886, was the date of a major general strike centered on Chicago, calling for an eight-hour workday.  Then of course May 4th was the Haymarket Riot in Chicago, where an anarchist crowd of German and Bohemian immigrants clashed with police, which explains why the US wants to celebrate workers any day of the year except in early May!