“May First”

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"May 1 became the Day of International Solidarity with Workers. On this day in in 1918, the Soviet government marked May 1 as Day of International Solidarity with Workers. Its origins date back to Australia in 1856, when workers demonstrated for an 8-hour work day"—https://www.themoscowtimes.com/2019/05/01/on-this-day-in-1918-soviet-russia-celebrated-may-1-a65456#:~:text=May 1 became the Day of International Solidarity with Workers&text=On this day in in,an 8-hour work day.
“May First”