The Kaganate (or the smaller tribal confederacy) was commonly built of leading Steppes Nomad tribes, subject Steppes Nomad tribes, subject agricutural and hunter-fisher (together henceforth called "settled") tribes of the region, vassal tribes (tribes owing Taxes to the Kaganate but not living within its "borders"), as well as tribes in more or less continuous relationships with the Kaganate (and thus influenced by, and influencing the culture of the Kaganate).

This article is an attempt at a list-form overview of three thousand years of Steppes Nomad history.
It is a work in progress -- Contributions to the article are welcome.

Where a more detailed article on a given tribe exists, a hyperlink is provided to that detailed article.

The Kurgans - To disappoint "Highlander" fans -- this is not a tribe.
A Kurgan is a burial mound - similar to the Barrows or "Fairy Mounds" of Brittain. The Kurgans were the method of burial used by the Steppes Nomads from the earliest times and into the High Middle Ages. For the Early Nomad cultures, the goods found in those mounds are fundamental to our knowledge of those cultures, while for the Medieval Nomads, the Kurgans offer a valuable suplement to other evidence.
(to help out "Highlander" fans -- the "Kurgan" character seems to have been a caricature Scythian)

THE ANCIENT STEPPES KINGDOMS

The Cimerians - This was an Iranian-speaking tribe which came down from the Eurasian Steppes into the fields of Eastern Europe in roughly 1000 BCE and was the leading force in the area until it was eclipsed by he Scythians.
Yes, this is the tribe of fantasy's famed Connan - although Connan is a Celtic name - not likely to have been used by them. To disapoint film fans further, the iron swords used by the Cimerians were light, long, one-handed swords with a small grip that would have been used with two fingers by the movie hero.

The Scythians - Likely closely related to the Cimerians, the Scythians came down from their ancestral lands in the Altai mountains in approximately the 8th century BCE, taking the place of the Cimerians.
Their chief deity seems to have been a snake-footed godess and, in Greek historiography, they were thought to be the descendants of Hercules and this godess.
Briefly making a bid for Persia, the Scythians settled in Eastern Europe where they controlled trade between the Greeks and the settled tribes of Eurasia (keeping a tight hold on Greece's wheat supply).
The Scythians were decimated by Philip of Macedon (the father of Alexander) and never recovered.
A number of tribes closely related to the Scythians remained to the East and North, closer to the Scythian ancestral areas.
- The Saka - One of the more famous of these, located in the area of modern Kazakhstan.
- The Amazons - Little is known about this tribe outside of the Greek legends. The name the Scythians used for them means "Man killers", which seems to back the legends.

The Sarmatians - Said by the Greeks to be the offspring of the Scythians and the Amazons, this new group of Iranian tribes came onto the scene as the Scythians declined, in roughly the 3rd century BCE.

THE MEDIEVAL STEPPES KINGDOMS

The Huns - This confederation of tribes was built solely on the strength of character of their leader -- the famed Attila. It began with his assent and ended with his death. In between, the Hunnic Kaganate took tribute from both Eastern and Western Rome.
Displacing, and likely incorporating, the Sarmatian tribes, the Huns incorporated what were to become the new Turkic and Uighur tribes that would thenceforth be the face of Steppes nomad culture.

The RED KAGANATE Begins - 560 CE

The Great Turk Kaganate - Considered by their Byzantine contemporaries to be the descendants of the Saka, the Turks entered the world stage in the second half of the 6th century.

From the begining, this confederacy was composed of two semi-autonomous nations - the White (Eastern) Turks and the Blue (Western) Turks who soon quareled and split into independant Kaganates.

The Blue Turks - The Western half of the original "Great Turk Kaganate", this kingdom controlled Eastern Europe and Western Central Asia and seems to have been the direct ancestor of the Khazar Kaganate.

The Uighur - These tribes formed several important empires in the Central and Eastern Steppes. Uighur groups are often named with a prefix added to the root Gur (ie: the Onogur).

Bulgars - The Bulgars entered the world stage in the 6th century CE.
The "Great Bulgar" Empire was established near the Caspian Sea, where the group that eventually converted to Islam came to be known as the Volga Bulgars.
 

The History of Bulgaria

A second group continued west and south, invading the region between the Danube River and the Black Sea now known as Bulgaria, where they formed a relatively small ruling class over a large Slavic population. Bulgaria was converted to Christianity in the 9th century under Kijnaz (king) Boris/Michael. The first Bulgarian Empire was a major rival to the Byzantines until it was conquered and absorbed by them in the 11th century. A second empire's brief flowering was cut short in the 14th century by the conquest of the Ottoman Turks.

Article on The Jewish Khazars

The Khazars - Picking up after the Blue Turks, the Khazars gained controll over a large part of the Caucas and Eastern Europe, building fortresses and cities to cement that controll.
 

Under triple pressure from the Russ, Byzantium, and Persia, they declined in the 10th century and were finally descimated by the Russ leader Svyatoslav, who then took to himself the title Kagan in immitation of the Khazar ruler.