In the First Age writings, we encounter six groups of Men.
The Three Houses of the Edain:
1. Bëorians 2. Haladin 3. Marachians
Another group counted among the Edain:
The Two Houses of the Easterlings:
5. Bórians 6. Uldorians
Most of these named for the ancestor who led them into Beleriand and thus into recorded history. However, we are told that each of these groups was just the “van” of their kin, and each had relatives left behind in Eriador and the East. In other words, Tolkien thought in terms of these First Age types (1,2,3,5,6) in the Third Age writings, and one new type that arose in the Third Age writings (4) was transposed back into the First Age.
Eriadorans & Northmen
Eriadorans & Northmen (esp. Éothéod)
To these must be added at least two groups: the Dúnedain (Númenóreans) and the Haradrim. The Númenóreans of course are Atlanteans, descended from the Bëorians and Marachians (majority Marachians) proper of Beleriand, intermingled, and of course with many unique gifts bestowed upon them when they relocated to Númenór, and a very unique history.
Interestingly, this gets us to 8 groupings of Men — just shy of that magic number 9 (rings for Mortal Men). But if you’re going to try to puzzle that out, remember that three of the nine went to Númenóreans (representing the Three Houses of the Edain?), leaving us to look for only 6 more.
Tolkien says next to nothing about them. I definitely do *not* imagine them as related to the Haradrim (Africans) but rather to the Easterlings, but the more I imagine about them, the more they become distinct from the Easterlings. Variag has a Slavic vibe and Khand has a Turkish or Mongolian vibe; make of that what you will. I listed them under both East and Far South in my documents because I imagined them as far-ranging mercenary types.