The Kipchaks, also spelled Qipchaqs, known as Polovtsians (Polovtsy) in Russian sources, were Turkic nomads and then a confederation that existed in the Middle Ages inhabiting parts of the Eurasian Steppe.

First mentioned in the eighth century as part of the Second Turkic Khaganate, they most likely inhabited the Altai region from where they expanded over the following centuries, first as part of the Kimek–Kipchak confederation and later as part of a confederation with the Cumans. There were groups of Kipchaks in the Pontic–Caspian steppe, China, Syr Darya, and Siberia. Cumania was conquered by the Mongol Empire in the early 13th century.

The Kipchaks interpreted their name as meaning "hollow tree" (cf. Middle Turkic: kuv ağaç); according to them, inside a hollow tree, their original human ancestress gave birth to her son. Németh points to the Siberian qıpčaq "angry, quick-tempered" attested only in the Siberian Sağay dialect (a dialect of Khakas language). Klyashtorny links Kipchak to qovı, qovuq "unfortunate, unlucky"; yet Golden sees a better match in qıv "good fortune" and adjectival suffix -čāq. Regardless, Golden notes that the ethnonym's original form and etymology "remain a matter of contention and speculation".

On the Kipchak steppe, a complex ethnic assimilation and consolidation process took place between the 11th and 13th centuries. The western Kipchak tribes absorbed people of Oghuz, Pecheneg, ancient Bashkir, Bulgar and other origin; the eastern Kipchak merged with the Kimek, Karluk, Kara-Khitai and others. They were all identified by the ethnonym Kipchak. Groups and tribes of possible Mongolic or para-Mongolic extraction were also incorporated into the eastern Kipchak conglomerate. Peter Golden argues that the Ölberli were pushed westwards due to socio-political changes among the para-Mongolic Khitans, such as the collapse of the Liao dynasty and formation of the Qara Khitai, and attached themselves to the eastern Kipchak confederation where they eventually came to form a part of the ruling strata and elite. Golden identifies the Ölberli with the Qay whom are recorded as the Xi in Chinese sources and Tatabı in Turkic inscriptions, and were of Mongolic or para-Mongolic background - likely stemming from the Xianbei.

Chinese histories only mentioned the Kipchaks a few times: for example, during Yuan dynasty Mongolian general Tutuha's origin from Kipchak tribe Ölberli, or some information about the Kipchaks' homeland, horses, and the Kipchaks' physiognomy and psychology.

The Kipchaks were first unambiguously mentioned in Persian geographer ibn Khordadbeh's Book of Roads and Kingdoms as a northernly Turkic tribe, after Toquz Oghuz, Karluks, Kimeks, Oghuz, J.f.r (either corrupted from Jikil or representing Majfar for Majğar), Pechenegs, Türgesh, Aðkiš, and before Yenisei Kirghiz. Kipchaks possibly appeared in the 8th-century Moyun Chur inscription as Türk-Qïbchaq, mentioned as having been part of the Turkic Khaganate for fifty years; even so, this attestation is uncertain as damages on the inscription leave only -čq (𐰲𐰴) (*-čaq or čiq) readable. It is unclear if the Kipchaks could be identified with, according to Klyashtorny, the [Al]tï Sir in the Orkhon inscriptions (薛延陀; pinyin: Xuè-Yántuó), or with the Juéyuèshī (厥越失) in Chinese sources; however, Zuev (2002) identified 厥越失 Juéyuèshī (< MC *kiwat-jiwat-siet) with toponym Kürüshi in the Ezhim river valley (Ch. Ayan < MCh. 阿豔 *a-iam < OTrk. Ayam) in Tuva Depression. Linguist Bernard Karlgren and some Soviet scholars (e.g. Lev Gumilyov) attempted to connect the Kipchaks to the Qūshé ~ Qūshí (屈射), a people once conquered by the Xiongnu; however, Golden deems this connection unlikely, considering 屈射's Old Chinese pronunciation *khut m-lak and Eastern Han Chinese *kʰut źa ~ kʰut jak/jɑk (as reconstructed by Schuessler, 2009:314,70). The relationship between the Kipchaks and Cumans is unclear.

While part of the Turkic Khaganate, they most likely inhabited the Altai region. When the Khaganate collapsed, they became part of the Kimek confederation, with which they expanded to the Irtysh, Ishim and Tobol rivers. They then appeared in Islamic sources. In the 9th century Ibn Khordadbeh indicated that they held autonomy within the Kimek confederation. They entered the Kimek in the 8th- or beginning of 9th century, and were one of seven original tribes. In the 10th-century Hudud al-'Alam it is said that the Kimek appointed the Kipchak king. The Kimek confederation, probably spearheaded by the Kipchaks, moved into Oghuz lands, and Sighnaq in Syr Darya became the Kipchak urban centre. Kipchak remnants remained in Siberia, while others pushed westwards in the Qun migration. As a result, three Kipchak groups emerged:

The early 11th century saw a massive Turkic nomadic migration towards the Islamic world. The first waves were recorded in the Kara-Khanid Khanate in 1017–18. It is unknown whether the Cumans conquered the Kipchaks or were simply the leaders of the confederacy of the Kipchak–Turkic tribes. What is certain is that the two peoples gradually mingled politically and that, from the second half of the 12th century onwards, the names Cumans and Kipchaks became interchangeable to refer to the whole confederacy.