May 1 demonstration, Union Square, NYC, 1933.
Union Square in New York City has become known as the focal point for labor and radical demonstrations. May 1 - or May Day - was recognized as the day when left-wing and union organizations initially held rallies on the Square, and later organized parades that ended in the northern area of the Square, where the participants heard speeches by the leaders of the demonstrating organizations. During the Cold War, an effort was made to convert May 1 into a "patriotic" holiday, but the effort fizzled out after a few years. Meanwhile, the annual May Day parades into Union Square had also become a part of history.
Courtesy Howard Greenberg Gallery, New York City.