"Who was the Spanish 'Flea'?"

In Part One, Scene V, of Faust, by Goethe, Mephistopheles, while in a tavern, sings a song about a black flea in the court of a king. In way of introducing the song, he mentions that he had recently been in Spain. I am wondering what was the source of the song?

At this point, I have deduced that the king must be King Charles IV of Spain and the “flea” could be Manual de Godoy, who rose up from the military ranks to become Prime Minister of Spain. While Godoy was in the favor of Queen Maria Luisa, it is written that his government was corrupt and that he was not well liked by citizens of Spain. In fact, according to one article I read, "....after Charles IV’s first abdication. Godoy who was captured and mauled by a mob in Aranjuez, was rescued by the French and sent to France. He died in Paris."

Can anyone confirm this theory or provide other information?

The text I am using is an English translation of Faust, in the original meters, by Bayard Taylor, which had an original copyright date of 1870. The words to the song are as follows:

MEPHISTOPHELES (sings)

“There was a king once reigning,
Who had a big black flea,
And loved him past all explaining,
As his own son were he.
He called his man of stitches;
The tailor came straightway:
Here, measure the lad for breeches.
And measure his coat, I say!

BRANDER

But mind, allow the tailor no caprices:
Enjoin upon him, as his head is dear,
To most exactly measure, sew and shear,
So that the breeches have no creases!

MEPHISTOPHELES

In silk and velvet gleaming
He now was wholly drest--
Had a coat with ribbons streaming,
A cross upon his breast.
He had the first of stations,
A minister’s star and name;
And also all his relations
Great lords at court became.

And the lords and ladies of honor
Were plagued, awake and in bed;
The queen she got them upon her,
The maids were bitten and bled.
And they did not dare to brush them,
Or scratch them, day or night:
We crack them and we crush them,
At once, whene’er they bite.

CHORUS

We crack them and we crush them,
At once, whene’er they bite.”

Thanks for any help!

Susan