The origin of the seven Swordgaunts are lost in myth, but the three most reliable sources are Kalshan and bar Mahhout, both scolars of the First Century of Enlightenment, and the Xantuul-fragments of the early Second Age.
Kalshan writes: "The Swordgaunt is a tall, gaunt figure clad in black full plate mail with a long cape made out of darkness and shadows. His face is pale, with a wax-like shine. His lifeless hair flows like strings of coagulated tar, and his eyes glow like the cold winter sun. On his head he wears a crown wrought of a dozen sharp blades. He wields the sword Kawnshuagh and a Nightmare serves as his steed." Here Kalshan is believed to speak of the witch-king Hanamog who held the city of Mulwar thrall around 450 BC. According to Kalshan, this feind were slain by the hero Abbanzar when he freed the city. It is this correspondent's believef that Kalshan mistakenly thought that the witch-king and the Swordgaunts were of the same ilk. This conclusion builds on an Orcish legend discovered in my journeys on the Dark Continent in the last days of the Old Colonies. The witch-king is also mentioned in the Bolianor, see below.
Bar Mahout writes: "The Swordgaunts, seven, once great heroes. Their armours, empty shells; their faces, forgotten memories. The seven, once heroes, now hollow men. Not blood but empty darkness in their veins. Not love but cold hunger in their hearts."
Both these sources clearly points towards a nature of soullessness, and as such unnatural to this world.
The oldest source that mentions the Seven is the Xantuul-fragments, pieces of three Second Age tablets, bearing the eulogy of King Humarrahim of the Illai.
The Illai was a great tribe in the First Age, and Humarrahim was their captain in the Great War. The fragments tell of seven great warriors who set out to destroy the Dark Queen of Gerem Faït, said to be a master of the elven art of naming. (Note that the Dark Queen is believed to be the same entity the Orc now worship as Mother) They were never seen again alive, but over the following Generation (here: Generation of the Exalted -- a period of time roughly four hundred years long) seven armoured warriors hunted the royal line of the Illai. Humarrahim was the last of his house, but the parts of the Xantuul-tablets that speaks of his fate are long lost (the fragments we have were lost earlier this year in an unexplained explosion that destroyed the Abbey of Nerwalt).
Various lesser sources claim that as many as five of the Swordgaunts may have been slain over the ages, but this cannot be held for certain. Keep in mind that the Erian Republic-era epic poem, the Bolianor, has Irendar slay the witch-king of Gerenfall already as early as in the sixth or seventh century BC.
The Swordgaunts appear here and there in tales and legends, but they seem to be bound primarily to the Dark Continent, with only brief and allegorical mentions of them in Erian culture. I write of these now so that if they too should reappear in this Dark Age, they be known to those they fall upon. Remember that in every myth there is a shard of truth, and that whatever has happened before shall happen again.