The Jotun & The First Born
The Jotun and their First Born are long lived, powerful creatures to rival the Aesir and the Vanir, and are just as ancient. They have caused many conflicts and strife to the Gods over the course of time, though they also interact peacefully as well.
The Jotun
The Jotun are a mighty race of beings, which come in two varieties; the Frost and the Fire. Many believe they are another race of Gods themselves, for they appear to live as long as the Gods do and have incredible power. However, most of the Jotun are not Deities for they do not have an attunement to a Rune. Some Jotun were born with an attunement to a Rune though this is a minority of cases; the most well known being Loki.
The Jotun, though often are made out to be powerful towering monsters are usually not that much larger than the Gods, and are just as enchanting. The main identifying feature, marking them as of the Jotun pursuasion, is either a blue or red tinge to their skin and their eyes, dependent on which family of Jotun they are from.
The First Born
The First Born refers to the first few generations of those who are born of both the blood of a Jotun Diety, and beings other than a God, such as Loki's children. This union has been known to bring about creatures that are outside of the normal remit of life; creatures that are monstrous in either size or visage. Nobody has yet discovered why they were born like this. Some are just as intelligent as their God and Jotun ancestors, able to talk and reason; such as Hel and Fenrir. Some are less so, intelligent but unable to communicate. The most well known are listed below, though it has been rumoured that more exist.
Their decendents are what turned into the Jotunborn.