Beginning in the late 19th century, as the trade union and labor movements grew, trade unionists proposed that a day be set
aside to celebrate labor. "Labor Day" was promoted by the
Central Labor Union and the Knights of Labor, which organized
the first parade in New York City.

By the time it became an official federal holiday in 1894, thirty
states in the U.S. officially celebrated Labor Day.

P. J. McGuire, Vice President of the American
Federation of Labor, is frequently credited as
the father of Labor Day in the U.S.

(From Wikipedia, the free encyclopedia)

Illustration of the first American Labor parade held in New
York City on September 5, 1882 as it appeared in the
September 16, 1882 issue of Frank Leslie’s Illustrated Newspaper.

On the morning of July 31, 1975, James Riddle Hoffa, one of
the most influential American labor leaders of the 20th century,
was officially reported missing after he failed to return home
the previous night.