International Workers' day
The story of the International Worker's Day for dummies
Long time ago at Haymarket Square ...
AND what's the meaning of MayDay?
"The first is the more traditionally understood radical and proletarian meaning of the term, dating by most accounts from the Marxist- and left-anarchist-led struggle for an Eight Hour Day in Chicago in the spring of 1886 – the conflict that led to the infamous Haymarket bomb, the hanging of the Haymarket Martyrs, and a terrible wave of anti-union and anti-Left repression across the United States." Paul Street, MayDay: Four Interrelated Meanings