Gwyn, Nito and The Witch of Izalith used the power procured from the Lord Souls to challenge the Everlasting Dragons for dominion of the world and, with the help of others, were successful in their endeavor.
The Witch of Izalith attempted to recreate her own First Flame by using her Lord Soul, but this resulted in her own demise and the creation of the Bed of Chaos, mother of all Demons, who inherited possession of the Soul.
The fourth Soul that was discovered by the Furtive Pygmy, ancestor to the Chosen Undead, was a unique Soul, the "Dark Soul". With it, he waited for Fire to subside so that the Dark Lord could one day be born amongst the humans and bring about the Age of Dark.
Soul of Gwyn, Lord of Sunlight and Cinder, who linked the First Flame.
Lord Gwyn bequeathed most of his power to the Gods, and burned as cinder for the First Flame, but even so, Lord Gwyn's soul is a powerful thing indeed.
Soul of the Bed of Chaos and the mother of all demons. This Lord Soul was found at the dawn of the Age of Fire.
The Witch of Izalith attempted to duplicate the First Flame from a soul, but instead created a distorted being of chaos and fire. Its power formed a bed of life which would become the source of all demons, and is more than enough to satiate the Lordvessel.
Soul of Gravelord Nito, first of the dead. This Lord Soul was discovered at the dawn of the Age of Fire.
Gravelord Nito administers the death of all manner of beings. The power of his soul is so great that it satiates the Lordvessel, despite the fact that much of its energy has already been offered to death.
Soul of one of the Four Kings, who fell to the Dark. A fragment of a Lord Soul discovered at the dawn of the Age of Fire.
Lord Gwyn recognized the foresight of these four great leaders of New Londo, and granted them their ranks and the fragments of a great soul. Although this is not a full Lord Soul, it can still satiate the Lordvessel.
Soul of the albino dragon, Seath the Scaleless. A fragment of a Lord Soul discovered at the dawn of the Age of Fire.
Seath allied with Lord Gwyn and turned upon the dragons; for this he was awarded Dukedom embraced by the royalty, and given a fragment of a great soul. Although just a piece, it will still satiate the Lordvessel.