I wasn't talking about an organization, I was talking about a movement. There are numerous different organizations of various sizes, as well as individuals, who are part of the movement.
None of this is new -- white nationalism has a long and well-documented history. As with all political movements, the exact moment it started is a little fuzzy. Some place it as far back as 1916 with the KKK, but I think that most people place the modern form of it as starting in 1974 with the National Alliance.
What point are you trying to get at? There are plenty of ideologies and political ideas that aren't represented by a singular organization advocating for them.
There are people of other ethnicities that are part of the White Nationalist movement.