Thanks, Steve. The article by Lyman that Gibb cites is pretty well known (well, to some people). Presumably it incorporates some later thoughts.

So far as it relates to "shanty/ chantey," Lyman's later article chiefly reports his discovery of the word "chantey-man" in Nordhoff. He offers only two bits of evidence to support a French derivation. First, "chantey-men" were known to Nordhoff in N.O. at the same time as the hoosiers were singing their own chants. (N.O. makes a French influence conceivable.) Second, Frederick S. Hill in 1893 recalls that fifty years earlier, in Mobile, the singing cotton-screwers were led by a man they called the "shantier," which Hill derives from

It is possibly significant that the first English appearance of "shanty/ chantey" is in the apparent compound "chantey-man" rather than standing by itself, but with so little evidence available it may mean nothing.

It would be much more impressive if there existed a French word in use in N.O. or the Gulf or Caribbean area that sounded something like "chanteyman" or "chantey gang" and also meant something vaguely related or relatable. In that case, "chantey" could have been a back formation from, say, "chanteyman." But there seem to be no candidates.