Who is credited with inventing the fictional races that we play in Everquest?

[Ele]

Each of those listed races have roots in old English, Germanic, and Norse mythology, albeit some slightly altered and some significantly altered from our current popular conception of these mythological races.

Tolkien's writings refreshed them in the pop-culture, and D&D adapted them to their fantasy games. It is difficult to tell if someone else would have written such a fantasy book that had such wide impact to revive these mythologies and create new ones in the way it has occurred over the last 70 years.