Mention of "Slane" (the hymn tune) reminds me of my take on it. There is/ was a comic character (Barbarian hero in the mold of Conan) in the British comic 2000AD, called Slaine.
The similarity of character name and tune led me to:

SLAINE

Slaine stands alone 'gainst the murderous hordes,
Who attack him on horseback with axes and swords.
With bare hands and feet, he will fight for what's right.
He may be a hero, but he's not all that bright!

Slaine's home is South Waest and a long way away,
So he follows the sun in its course through the day.
His way he plots clear t'ward the pole star each night.
As I may have mentioned, He's not all that bright.

Unfortunately, the envisioned third verse never came to fruition. Ah well!

Nigel