The Barrow-Song

Hide away the night, don't stay there too long, oh here comes the wight, sing the barrow-song. Run, run far away and sing the barrow-song
Run or you'll be dead, you won't live for long, for there are the wights, sing the barrow-song. Run, run far away and sing the barrow-song.

— Two verses from the Barrow-Song

The Song of a dark memory

To the west of Aruël lie the Razortooth mountains, which form a natural barrier halting any Aruëlian conquest. Unbeknownst to them, this mountain range has performed similar functions all throughout history. For our story today, the relevant occasion was Osylana, the halfelven realm. Osylana dominated the eastern half of the continent, with their western border hugging the same mountains. There they erected The Osylanian Nekropolis, a dangerous and vast network of interconnected barrows.

Campfire stories by Ninodonlord (via Midjourney)

Here they entombed the worst of the worst of their society as well as the people who fell in battle. It is unknown if the Osylanians did this to avoid what would become a serious problem. If a person dies with unresolved issues, anger and resentment primarily, their body may refuse to roll over and decompose. They become a husk of a person, bent on achieving that goal. Unfortunately, many of them are denied that accomplishment forever and as a result they cannot pass on. They become a shade of their original person, barely remembering anything except for the unrelenting driving goal that keeps them standing. The monster resulting from this is called a wight

The breaches

While Osylana stood, this system worked out relatively well. The undead most likely to become wights were contained in a place that they could not escape. Then the Ksrizka conspiracy and the Myconic Plague struck in quick succession and wiped Osylanians and humans in general off the map. Milennia passed before anything resembling a human set foot in the lands of Noria again. When they did they found the strange ruins of Osylana and eventually also spread to the barrows and hills at the feet of the Razortooth ranges.
Despite the abyss of time and lost knowledge, the new human farmers and foragers, barely a tribal civilisation, still understood the danger coming from the barrows, based on the inhospitable design of the above ground structures, and the evil oozing from the earth. However, eventually someone had to make the first mistake. A barrow was breached and the wights inside released. The milennia inside had made them feral even more, most of them having lost their chance at fulfilling their goal, now cursed with unending existence. Lost in their anger the wights had a new release for it. The living.

The consequences

The release of wights upon the land was more dangerous than expected. They terrorized nearby settlements yes, and even killed. But the most horrifying consequence was the mark. Anyone who had dared breach a tomb was afflicted with the withering touch, a mark that draws wights like light draws moths. To the best knowledge of the humans, there is no cure to the touch.
Because of this danger, the livings society adapted, social stigmas and rules were created, to never even approach the barrows, a byproduct of which was the song mentioned in the beginning. Additionally, the local experts in mysticism developed ways of containing and dealing with released wights, eventually finding a path that allowed the restless souls to finally find peace and move on. Nonetheless, the fear of the barrows has burned itself into the instincts of many sapient species in the area, so much so, that almost none dare venture there today.

Unexpected Links

Darkness over Barrows

Cowered in fear, we sit round the flame
And darkness falls over barrows.
Slowly creeps cold in from the night
And darkness falls over barrows.
Never before, we dared go to fight
The monsters that roam in the barrows.
Now we are lost and none are to blame,
As darkness it seeps out the barrows.

The text to the left is an orcish poem which seems to describe almost exactly the same scenario. It is likely, that the memory of the undead plight upon the land burned itself into the memory of more than one species.

It is possible, that orcs were involved in the initial opening and venture into the barrows, upon which some of them contracted the withering touch, marking the tribes they returned to as targets for the undead
In the end, the undead were overcome, but not before both man and orc suffered greatly

Given the length that Osylania existed and entombed its dead here, the Barrows will perhaps never be emptied and even in the next civilisation to grace these hills, will people try to understand what happened in these hills to cause such darkness.