The Göktürks behead three thousand Rouran in 555.

Some scholars claim that the Rouran then fled west across the steppes and became the Avars, though many other scholars contest this claim.

The remainder of the Rouran flee into China, are absorbed into the border guards, and disappear forever as an entity.

The last Rouran khagan flees to the court of Western Wei, but at the demand of the Gökturks, Western Wei executes him and the nobles that had accompanied him.

The Gökturk expansion also pushes against the Avars, who are driven toward the East Roman Empire and the Sassanid Empire and eventually toward the Danube.

Other tribes of Central Asia, such as the eastern Bulgars, are also displaced.

A new nation, that of the Turks, has emerged in the east.

The seat of the western part of the Turk Empire founded by Bumin in 552, ruled by Bumin's brother Istämi, lies in Ektagh, an unidentified place, possibly in either the Ili or Chu river valley.

Istämi establishes diplomatic relations with Constantinople in 558.

The Sassanid monarch Khosrau of Persia, by concluding an alliance with a Turkish leader called Sinjibu (Silzibul), is able with Turkish help to attack and destroy the Hephthalite empire in 560.

The Western Gökturks establish a common frontier with Persia, thereby gaining control over an important portion of the Silk Road leading from China to Constantinople.

Procopius claims that the White Huns live in a prosperous territory, and that they are the only Huns with fair complexions.

According to him, they do not live as nomads, do acknowledge a single king, observe a well-regulated constitution, and behave justly towards neighboring states.

He also describes the burial of their nobles in tumuli, accompanied by their closest associates.

This practice contrasts with evidence of cremation among the Chionites in Ammianus and with remains found by excavators of the European Huns and remains in some deposits ascribed to the Chionites in Central Asia.

Scholars believe that the Hephthalites constituted a second "Hunnish" wave who entered Bactria early in the fifth century, and who seem to have driven the Kidarites into Gandhara.

Istämi, who bears the title yabghu of the western part of the Gökturk Khaganate, collaborates with the Persian Sassanids to defeat and destroy the Hephthalites, who had been allies of the defunct Rouran Khaganate.

After a series of wars in the period 503–513, the Hephthalites are driven out of Persia and completely defeated in 557 by Khosrau I.

Their polity will hereafter come under the Göktürks and subsequent Western Turkic Khaganate.

This war tightens the grip of the Gökturks’ ruling Ashina clan on the Silk Road.