Why Mount Mirthless is barren

"Would you fair maiden ponder my plea, leave your lonely herding and run oft with me, I'll buy you a wedding gown, of pearls and silk threads, of dove down and moonlight, if you'd be my Lady wed.~"

— The Lord of Mirth's Love song

Summery

Why Mount Mirthless is barren is a tragic love story and an explanation of why said mountain is so inhospitable. The tale begins with a handsome man in plains clothing approaching a shepherdess and asking to court her. She tells him that she is beholden to her herd and cannot abandon it but to come again next week. The man who is named Starling peddles his bardic skill at the tavern and square untill next week. He meets her again as she asked and requests again to court her, she repeats another excuse week by week becoming more and more ridiculous and in a fashion implying that she does want to court by asking him to return.
In some tellings this continues the same for the whole story but in others she eventually asks him to escort her home for some excuse or another. This then repeats with him continuing to tell her poetry and give her gifts such as fine gloves and shawls to keep her warm and a magic bell that will allow her to always find her sheep. Soon afterwards a powerful young man, sometimes simply a rich one other times he is the son of an elder or the mayor as well becomes overcome with jealousy.
The jealous man procures a charm from a winter spirit that is unspecified but strongly implied to be malignant. This charm allows him to sneak into Starling's lodgings to discover foxes sweeping the floor. Thanks to the charm he went unnoticed and overheard them speaking of their masters courtship of the shepherdess. Armed with this knowledge he went to the town and explained he had seen the strangers fox servants and that Starling was obviously some trickster spirit that would bring the town harm.
Since the man was well known and well regarded the town was easily convinced and they went to the shepherdess's hut armed with salt, fire, and iron. When the mob approached they saw starling with the shepherdess holding starlight in his hand and knew that he indeed was a not a mortal man.
They tossed salt and waved fire at Starling but he was unaffected, he asked "why do you toss that better saved for the winters darkness at me?" and the villagers told him that they knew he was a trickster and to leave. Starling turned to the mob but the shepherdess put a hand to his shoulder and asked him not to fight, that they were foolish but did not mean for evil. She promised that she would sell all her sheep that spring and come to him at the brook on the mountains foot and they could be wed then and their. As long as her sheep were seen after.
Starling agreed and shed mortal skin revealing himself as the Lord of Mirth. Before he left though he put a term to his departure.

"I leave with the my beloved. In thy care I leave her and into my care shall she come when her sheep have a new master."

And with that he took his leave.
Unsure of themselves the mob broke apart and went home. The rich young man tried to speak with the shepherdess but she scorned him fiercely and nothing more happened for many weeks. In the midst of winters howling, when the dark clawed at the door to the dwelling and the heart in equal measure it wrought misery invited. A dark whisper urged snow to pile and ice to grind the storehouse's roof and while some went to fetch the midwinter's mead the beams cracked and all died save one.
The survivor was saved only by keen ears that heard the storehouses crash and did not wake. Every villager from the greyest grandmother to the stumbling infant had searched that storehouse for the smallest fault.

Had we searched it less or had the beams as much as squeaked so would we blame time. But every hand has tested every beam so someone has met something malicious.

The rich young man's familiy had built the storehouse so they asked him first. "Have you met some stranger and made some offince or struck some deal?" And while he had gone to that winter spirit and bought the charm that let him slip hither and thither unseen he did not wish to admit fault and denied such.
At first they did not question the shepherdess for the spirit she met they thought was the Lord of Mirth and that Lord is good for their word. But as the folk talked they realized that none of them had met any stranger that could have wrought this and so they began to argue amongst themselves. The rich young man was afraid that they would begin to wonder how he had known Starling was not a human man and now the townsfolk were angry so he sought to throw them off.

Could it not be that the spirit that wooed the shepherdess was not the Lord of Mirth in truth? She is the only one we know that has cavorted with a spirit.

The villagers did not want to go against the rich young man so they accepted this as reasonable even though they had seen the Lord change shape and fly away.
So they commanded the shepherdess to rub herself in salt and sit right by the fire to drive the curse away and she agreed. She said that her beloved was no dark spirit but you have sent him away from the mountain wholly and so some dark one may hold some grudge to me from him. But the rich young man did not want the town to seek out the spirit he had dealt with so he said she must be mistaken and in his selfishness and jealousy he suggested her things be burnt to wipe the spirits influence and that she be confined from leaving the mountain.
With the fear and hatred of the dark clinging to him and from the hatred and fear of the town boiling the suggestion became a demand.
When the shepherdess denied their madness and called it such the anger and fear made the demand a demand or else. The rich young man feared and would not reveal his lie, thus evil was done. The townsfolk would not heed what all knew was true of spirits and let their fear turn to cruelty, thus evil was done. So the fear became hate and the hate became violence and the violence became murder and so they beat the shepherdess and turned her out on the stoop and so she died.
But she did not die alone with her murder unwitnessed. There was a single fox that had stayed with her masters beloved as her handmaid yet because of the rich man's charm she saw no evil until her strength was sapped that night by the dark. Try as she might the fox could not keep her mistress warm and she perished still.
With weeping in the rays of dawn the handmaiden fled down the mountain and told the Lord of Mirth of what had happened. In a rage the Lord flew up to the village in a rage and struck all but the unconscious man who could not have been responsible for murder and the children who could not be as well. So there was some left to warn of what happened.
Sense then the Lord of Mirth has be named the Lord of Mischiefs as bitterness was brambles on his heart and the whole of all humans had to flee the mountain for it would feed them no more. The only thing of man left there was the shepherdess's sheep that flourished with health and cleverness like none other.