Akaviri

The Akavir, more commonly known as the Akaviri, were a humanoid race from the continent of Akavir. They spoke a language known as Akaviri. There are several theories about the Men of Akavir, that they died out long ago, were eaten by the Tsaesci, or that they are in fact the Tsaesci themselves.

Anthropology
It is not known exactly where the Men of Akavir came from, but some say they were Nedic settlers from Atmora, like the ones that settled in Tamriel. Wherever they may have come from, they have long since died out as of the present, as they were eaten long ago by the Tsaesci ("eaten" may not refer to literal ingestion - some believe that the Tsaesci merely assimilated the Akaviri).

Physiology
The Akaviri are believed to have been much like other human races in terms of physiology and appearance. While it has not been confirmed as to what colour their skin was, it was believed that they looked like all the other races of Men in terms of shape. In one instance in 2920, Morning Star (v1), they are referenced as being serpentine, as well as one Akavir being "anal intercourse glistening ivory-yellow eel" (Although this is almost certainly referencing the Tsaesci).

Culture
Little to nothing is known about the culture of the Men of Akavir, other than the fact that they seem to heavily mirror Asian culture through their armor, weapons, and buildings. Cloud Ruler Temple, in Cyrodiil, is based on Akaviri design, as well as the armor of The Blades. The Akaviri also seemed to have used katanas, a traditional Japanese armament. This is because The Blades, usually thought of as the Emperor's bodyguards, originated as Akaviri crusaders who invaded Tamriel for obscure reasons in the late First Era. They appear to have been searching for a Dragonborn - the events at Pale Pass bare this out - and the Akaviri were the first to proclaim Reman Cyrodiil as Dragonborn. In fact, it was the Akaviri who did the most to promote his standing as Emperor (although Reman himself never took that title in his lifetime). There is no known hereditary connection between Tiber Septim and any of the previous Dragonborn rulers of Tamriel.

History
Little to nothing has been preserved of the culture of the Men of Akavir. The Red Dragon, the symbol of the Septim Empire, came from the Akavir. During the Dragon War, the Akaviri built Sky Haven Temple in Skyrim as an outpost for their Dragonguard.

Trivia

 * The Septim Empire adopted the Red Dragon symbol
 * In the Soul Cairn you may encounter a soul mentioning an Akaviri Shaman trapping his/her soul.