What exactly do these childrens' rhymes mean?

I was doing a bit of research online the other day, hoping to expand my repertoire of lullabies and kid's rhymes and what I discovered was alarming.

Many of the songs and nursery rhymes we sing to our babies, and have been singing for decades, are more than slightly sullen. And after having given it a little thought, I became very curious about what's behind these glum lyrics that have been put to perky rhythms--where did these popular little ditties come from? These are songs that I have been singing since I was a tiny girl, and it never even occurred to me to inquire what the words even meant.

Let's take "Ring Around the Rosy" as the first example. A song loved by sweet little girls in sundresses everywhere who dance in a circle as they sing until the end when they all fall down in a heap of giggles. An image not at all congruous with the actual historical origin of the song: the Bubonic Plague.
Apparently the symptoms of the plague included a rosy red rash in the shape of a ring on the skin (Ring around the rosy). Pockets and pouches were filled with sweet smelling herbs (or posies) which were carried due to the belief that the disease was transmitted by bad smells. The term "Ashes Ashes" refers to the cremation of the dead bodies!
Oye.

And this is just the beginning.

Let's talk about "Rock-a-Bye-Baby."
The lyrics are said to reflect the observations of a young pilgrim boy who had seen Native Indian mothers suspend a birch bark cradle from the branches of a tree. Thus enabling the wind to rock the cradle and the child to sleep!
Rock-a-bye baby in the tree top.
When the wind blows, the cradle will rock.
When the bow breaks, the cradle will fall
and down will come baby, cradle and all.
Egads. Not exactly he image I want to plant in my little one's head as she is drifting off to sleep. Sweet dreams, sweetie. Don't' forget to wear your helmet.

Humpty Dumpty is one that my interpretation was, thankfully, much worse then the actual meaning. I thought it was about a fragile egg-shaped man who fell off a wall and broke into a thousand pieces. A devastating and depressing scene of that which is entirely unfixable:
Humpty Dumpty sat on a wall,
Humpty Dumpty had a great fall.
All the King's horses, And all the King's men
Couldn't put Humpty together again!
And even though Humpty Dumpty was a colloquial term used in fifteenth century England to describe an obese person, that's not what it's describing in this particular rhyme. Humpty Dumpty was actually believed to be a large cannon used in the Civil War between the Royalists and the Parliamentarians, belonging to the Royalists. When it "took a great fall" from the wall, it broke and could not be fixed, thus causing the Royalists to be forced to lay down their arms!
In spite of being happy to discover this rhyme is not about a egg-shaped man who jumped to his demise from a random wall, I still find it to be a bit serious for a kid's song.

Baa Baa Black Sheep is worth considering.
Baa, baa, black sheep,
Have you any wool?
Yes sir, yes sir,
Three bags full.
One for the master,
One for the dame,
And one for the little boy
Who lives down the lane.
Pretty straightforward, though there is some speculation about the "Little boy who lives down the lane" being a reference to the slave trade. Apparently there was an attempt to reform any non-politically correct nursery rhymes in the 1980's, and this was one on the list. But any reformation was not lasting.

Let's finish off our discussion with the ever-popular "Jack and Jill".
I can remember loving this one for the same reason I loved "Ring Around the Rosey"--it had a known choreography that went alongside the lyrics, it was a full-participation rhyme.
While we chanted:
Jack and Jill ran up the hill to fetch a pail of water,
we ran as fast as we could up whatever slight incline we could find.
Then, with Jack fell down and broke his crown and Jill came tumbling after, we would roll down the same hill and wind up in a silly mound at the end of the lyric and the bottom of the hill.
But with the slightest investigation, I learned that Jack and Jill came from an oh-so gruesome historical event that someone somewhere deemed appropriate for an upbeat children's jingle.
Fasten your seat belts for this one:
Jack and Jill referred to are said to be King Louis XVI - Jack -who was beheaded (lost his crown) followed by his Queen Marie Antoinette - Jill - (who came tumbling after).
My heavens.
I don't know about you, but I will have a hell of a difficult time singing this little cadence with a straight face from here on out.

So there you have it.
A handful of interesting discoveries on the origins of many of the catchy verses I've been reciting since I was barely potty trained.

It's one of those cases where it's probably better not to know, because I'm not quite prepared to compile a list of my own to replace the classics. But if I do, I will surely not base them on the highlights from my most distressing moments.