Who is McCoy from Albion's Seed: Four British Folkways in America and what is their importance?

The McCoys are infamous for being the other half of an interfamilial feud so intense and well-recorded that it has been enshrined by a popular song. As a consequence the Hatfields & McCoys are now frequently perceived as being a special kind of unity, despite the fact that their unity is based in protracted strife.

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