Etymology - Labor

The word labor means "exertion of the body," and comes from the french word labour which means "toil, pain, exertion, fatigue, work," perhaps originally "tottering under a burden," related to labere "to totter." the wider sense being taken by the equivalent of English travail. Meaning "body of laborers considered as a class" is from 1839.
Its roots seem to come form 1595 and term Labor in the Sense of "physical exertions of childbirth" . The first celbrated Labor Day was in 1882 in New York City.