"John Barleycorn" is an English folksong. The character of John Barleycorn in the song is a personification of the important cereal crop barley and of the alcoholic beverages made from it, beer and whisky. In the song, John Barleycorn is represented as suffering attacks, death and indignities that correspond to the various stages of barley cultivation, such as reaping and malting.
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... which is the baking of barley bread into the figure of a man known as John Barleycorn, who is referred to by the baker as "The life of the fields" ...