The following are unconfirmed, historians please correct any error here.
I heard that the US used to celebrate Labor Day on May 1 back in the 1920's.
However, May Day is a big holiday in communist countries.
The Americans wanted to disassociate themselves from communism and moved their Labor Day.
This change probably was a result of McCarthyism?, or perhaps just a general healthy anti-communism.
- Well, McCarthyism? per se was long after the 1920's, and the degree to which anti-communism is "healthy" is certainly open to debate.
I found one web page claiming that the unusual date for Labour Day in the US and Canada stems from an early-September event in Canada that led to the repeal of a ban on unions, and that the US picked it up from there:
http://www.perf.bc.ca/cep1092/labday.htm
No idea if it's true or not, but there you go. -- Paul Drye
It's pretty silly to have articles on both Labour Day and Labor Day.
I think that they should be merged. --
Taw