Why do we celebrate Labor Day? So Grover Cleveland could own the left.

We also celebrate workers and the labor movement on a completely different day from most of the rest of the world: Labor Day vs. May Day. That is particularly strange considering both days started right here in the United States. So how did one spread elsewhere while the other became a federal holiday here?

Politics, of course.

Labor Day came first, but its origins are contested, according to a widely cited 1982 paper by Theodore Watts. Some say it was the brainchild of a respected union leader, Peter McGuire, at an 1882 meeting of the New York Central Labor Union. Others credit Mathew Maguire, also a respected union leader and member of the New York Central Labor Union but with a reputation for radicalism. Watts and others suggest that after Labor Day became a big deal, union brass credited McGuire instead of Maguire in the origin story to keep any hints of radicalism at bay.

In any case, someone suggested a parade and picnic to celebrate workers and unions at a meeting in New York in 1882.

It went so well that organizers decided they would do it again the next September. Within a few years, it had spread to other states and cities and was moved to the first Monday in September.

Both May Day and Labor Day were honored in the United States by various labor groups for years, though the former had a reputation for being more political, more radical and less merry than the latter. For that reason, Labor Day was always more popular with lawmakers, and more than 20 states had made it a state holiday by 1894.

Making it a federal holiday was not high on the list for President Grover Cleveland. In 1894, he was focused on the recession and kicking around the idea of running for a third term.

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