The Pechenegs were mentioned as Bjnak, Bjanak or Bajanak in medieval Arabic and Persian texts, as Be-ča-nag in Classical Tibetan documents, and as Pačanak-i in works written in Georgian.

[4] Pechenegs are mentioned as one of 24 ancient tribes of Oghuzes by 14th-century statesman and historian of Ilkhanate-ruled Iran Rashid-al-Din Hamadani in his work Jāmiʿ al-Tawārīkh ("Compendium of Chronicles") with the meaning of the ethnonym as "the one who shows eagerness".

On the basis of their fragmentary linguistic remains, scholars view them as Common Turkic-speakers, most probably Kipchak (Németh, followed by Ligeti)[12] or Oguz (Baskakov).

[16][17] Mahmud al-Kashgari, an 11th-century man of letters who specialized in Turkic dialects argued that the language spoken by the Pechenegs was a variant of the Cuman and Oghuz idioms.

[18] He suggested that foreign influences on the Pechenegs gave rise to phonetical differences between their tongue and the idiom spoken by other Turkic peoples.

[22] Byzantine emperor Constantine VII Porphyrogennetos lists eight Pecheneg tribal groupings, four on each side of the Dnieper river, reflecting the bipartite left-right Turkic organization.

Pritsak says that the Pechenegs' homeland was located between the Aral Sea and the middle course of the Syr Darya, along the important trade routes connecting Central Asia with Eastern Europe, and associates them with Kangars.

[29] The report recorded an armed conflict between the Be-ča-nag and the Hor (Uyghurs or Oghuz Turks) peoples in the region of the river Syr Darya.

[29][32] Ibn Khordadbeh (c. 820 – 912 CE), Mahmud al-Kashgari (11th century), Muhammad al-Idrisi (1100–1165), and many other Muslim scholars agree that the Pechenegs belonged to the Turkic peoples.

[33] The Russian Primary Chronicle stated that the "Torkmens, Pechenegs, Torks, and Polovcians" descended from "the godless sons of Ishmael, who had been sent as a chastisement to the Christians".

[36] The Uighur envoy's report testifies that the Oghuz and Pecheneg waged war against each other already in the 8th century, most probably for the control of the trade routes.

[36] The Oghuz made an alliance with the Karluks and Kimaks and defeated the Pechenegs and their allies in a battle near the Lake Aral before 850, according to the 10th-century scholar, Al-Masudi.

According to Gardizi and other Muslim scholars who based their works on 9th-century sources, the Pechenegs' new territory was quite large, with a 30-day-walk extension, and were bordered by the Cumans, Khazars, Oghuz Turks and Slavs.

[29] In addition to these two branches, a third group of Pechenegs existed in this period: Constantine Porphyrogenitus and Ibn Fadlan mention that those who decided not to leave their homeland were incorporated into the Oghuz federation of Turkic tribes.

[...] At the time when the Pechenegs were expelled from their country, some of them of their own will and personal decision stayed behind there and united with the so-called Uzes, and even to this day they live among them, and wear such distinguishing marks as separate them off and betray their origin and how it came about that they were split off from their own folk: for their tunics are short, reaching to the knee, and their sleeves are cut off at the shoulder, whereby, you see, they indicate that they have been cut off from their own folk and those of their race.However, it is uncertain whether this group's formation is connected to the Pechenegs' first or second migration (as it is proposed by Pritsak and Golden, respectively).

The Uzes, another Turkic steppe people, eventually expelled the Pechenegs from their homeland; in the process, they also seized most of their livestock and other goods.

The Pechenegs were so successful that they drove out the Magyars remaining in Etelköz and the Pontic steppes, forcing them westward towards the Pannonian plain, where they later founded the Hungarian state.

Although an important factor in the region at the time, like most nomadic tribes their concept of statecraft failed to go beyond random attacks on neighbours and spells as mercenaries for other powers.

The Pecheneg wars against Kievan Rus' caused the Slavs from Walachian territories to gradually migrate north of the Dniestr in the 10th and 11th centuries.

According to Mykhailo Hrushevsky (History of Ukraine-Ruthenia), after its defeat near Kiev the Pecheneg Horde moved towards the Danube, crossed the river, and disappeared out of the Pontic steppes.

In 15th-century Hungary, some people adopted the surname Besenyö (Hungarian for "Pecheneg");[citation needed] they were most numerous in the county of Tolna.