Where does the term “John Barleycorn” come from and What does John Barleycorn mean?

The legendary gentleman John Barleycorn, sometimes styled Sir John Barleycorn, was apparently conceived about the year 1620.

That we gather from the use of the name as a title to “A pleasant new ballad of the bloody murther of Sir John Barleycorn,” of that period.

And the gentleman, if so he was, was even then a personification of malt liquor, or the grain of which it was made. But it is not likely that his name would still be known were it not for Robert Burns.

“Inspiring bold John Barleycorn,” he wrote in “Tam o’ Shanter,” “What dangers thou canst make us scorn!” See also his poem “John Barleycorn.”