The Shi'ar are an extraterrestrial semi-humanoid race who have established a galaxy-wide empire in the so-celled Shi'ar Galaxy and have had dealings with humans from Earth. The Shi'ar originated on a planet they call the Aerie (English translation) and their civilization predates Earth humans' recorded history. Shi'ar have both avian and mammalian characteristics: for example, although Shi'ar are outwardly humanoid and mammalian in form, they have feathers instead of hair. At an earlier point in their evolution the Shi'ar's had fully developed wings attached to their arms, enabling them to fly. (The current Shi'ar Empress, Deathbird, is an evolutionary throwback who possesses these functional wings.) Shi'ar females have mammary glands and are viviparous. Shi'ar are physically stronger than Earth humans: the average Shi'ar can lift (press) about one ton. Shi'ar also have twenty times as much endurance as an Earth human (this difference is comparable to that between an Earth bird and an Earth human). Apparently the Aerie's environmental conditions are similar to those of Earth, since Shi'ar can exist on Earth without artificial aids.

Since no Earth human except for Major Christopher Summers has ever piloted a spacecraft to the Shi'ar Galaxy, its exact location remains unknown. It is, however, believed to exist within the area of space containing the galaxy known on Earth as M-31. The Shi'ar now control all known inhabited worlds within their galaxy. Their principal rivals for control of the galaxy were the Mephitisoids who are now fully under Shier domination. The Shi'ar Empire is relatively young compared to those of the Kree and Skrulls, for the Shi'ar achieved control of their entire galaxy comparatively recently, and their empire is still in its main expansionist stage. Deathbird and the large Shi'ar military complex are both in favor of expanding Shi'ar rule into other galaxies, although during her short reign Lilandra Neramani proved to be s moderating influence on such ambitions. The recent changes in the possession of the Shi'ar throne, however, as well as the process of adjusting to governing a galaxy wide empire have kept the Shi'ar too occupied with internal affairs to pursue further conquests.

The Kree, Shi'ar, and Skrull Empires are the three major interstellar empires in the known universe. The Shi'ar have diplomatic relations with both the Kree and Skrulls, and due to the great distance between galaxies and the age-old hatred between Kree and Skrulls, have managed to avoid wars with either.

The Shi'ar Empire is governed from the Imperial Throneworld, an artificial planet constructed by the Shi'ar. Different artificial environments have been created on the Throneworld to serve the needs of the representatives from the numerous worlds within the Empire. The Shi'ar give the worlds they rule differing degrees of autonomy depending on various factors, notably their loyalty to the Empire. Some worlds have virtual independence, and are allowed to send representatives to serve on the Shi'ar High Council. Others, such as that of the Mephitisoids, ere kept under virtual martial law. The Shi'ar High Council acts as an advisory body to the Shi'ar majestor (emperor) or majestrix (empress) but complete executive power resides solely with the majestor or majestrix. The Shi'ar Imperial Guard, comprised of specially powered beings from throughout the Empire, act as enforcers of imperial Law. An elite corps of the Guard protects and carries out the personal directives of the majestor or majestrix. A much larger division, called the Borderers, aids the governors of conquered worlds in enforcing Shi'ar law on those worlds. The Shi'ar have an enormous interstellar fleet, used for military and exploratory purposes. Non-Shi'ar from loyal worlds are allowed to serve in the space fleet in positions below command levels. Members of conquered races that are regarded as primitive or of dubious loyalty are often used as slaves. Rebel leaders are consigned with criminals to "slave pits."

The eldest living heir to the Shi'ar throne was the female known as Deathbird who had been exiled for the crime of regicide. The throne went to her next oldest sibling, D'Ken, who proved to be insane and nearly destroyed the universe with the M'krann Crystal. His younger sister, Lilandra, then grand admiral of the imperial fleet, opposed him, and a civil war erupted Lilandra next ascended the throne, but was deposed in a coup led by Deathbird aided by the Badoon and the Brood. The High Council was dissolved, and most of its members killed. Deathbird now rules alone.

Shi'ar technology is extraordinarily advanced. Besides their advanced warp-drive starships, the Shi'ar can travel instantaneously between even galaxies using a space-warping device called the Stargate, which demands, however, far more energy than warp-drive starships.

The Shi'ar have known of Earth for many years and have secretly stationed observers there ever since it became widely known that it lay at a crossroads for hyperspatial routes within the Milky Way Galaxy and between that galaxy end those of the Kree, Shi'ar, end Skrulls. The Shi'ar tend to regard Earth humans as primitives, but some Shi'ar have begun to alter that opinion due to contact with Earth's X-Men. Former majestrix Lilandra has even taken an Earth human, Charles Xavier as her consort.

First appearance: X-MEN #97