Here is a verse of In Days of Old that I will admit to inventing at the age of 14 or so:

In days of old
When knights were bold
And heaters not invented,
The local whore was paid much more,
And not at all resented.

I grew up in Minnesota, so perhaps I was influenced by the weather.

Here is a much better little ditty on a medievil theme that I learned from my father. I think it was quite popular when he was in school (the thirties and forties). If so, it seems to show that the sophistication of our doggeral has declined perceptibly along with our educational standards. Not that all verses are that sophisticated, but a few of them are rather cleaver. There are supposedly many, many verses to this thing, but my dad, alas, only knew a few of them:

The King's Castration

'Twas the night of the King's castration
The royal ball was coming off.
And all the dukes and counts and no-accounts
Were there in their carriages and miscarriages.

"Where is Daniel?" cried the King.
"Daniel is in the lion's den."
"Bring Daniel fourth."
But Daniel slipped on a lion turd and came fifth.

"Oh shit!" cried the King
And a thousand loyal subjects dropped their drawers and strained.

"Where is the Queen?" cried the King.
"The queen is in bed with laryngitis."
"Last week it was Arthur Itus. They must be brothers!"
. . .
"Balls!" cried the Queen.
"If I had t[w]o I'd be King."