Although there is debate about the origin, it is widely believed that this rhyme refers to the Great Plague of London in 1665. The first line of "Ring Around the Rosie" is a reference to the physical symptoms that occurred with the "Black Death." The center would turn black with a reddish coloring surrounding it, hence the "ring around the rosie." A "pocket full of posies" is interpreted as the attempt to cover up the smell of the impending death with flowers, and the line of "ashes, ashes, we all fall down" is, hopefully, self-explanatory. It certainly puts a morbid spin on an otherwise classic nursery rhyme.
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