Ukrainians (Ukrainian: українці, romanised: ukraintsi, pronounced [ʊkrɐˈjin⁽ʲ⁾ts⁽ʲ⁾i]) are an East Slavic ethnic group native to Ukraine. Their native tongue is Ukrainian, and the majority adhere to Eastern Orthodoxy, forming the second largest ethno-linguistic community. At around 46 million worldwide, Ukrainians are the second largest Slavic ethnic group after Russians.

Ukrainians have been given various names by foreign rulers, which have included Polish–Lithuanian Commonwealth, the Habsburg monarchy, the Austrian Empire, and then Austria-Hungary. The East Slavic population inhabiting the territories of modern-day Ukraine were known as Ruthenians, referring to the territory of Ruthenia; the Ukrainians living under the Russian Empire were known as Little Russians, named after the territory of Little Russia.

The ethnonym Ukrainian, which was associated with the Cossack Hetmanate, was adopted following the Ukrainian national revival of the late 18th century. The Cossacks are frequently emphasized in modern Ukrainian identity and symbolism, such as in the Ukrainian national anthem. Citizens of Ukraine are also called Ukrainians regardless of ethnicity, and many identify themselves as a civic nation.

The modern name Ukraintsi (Ukrainians) is derived from Ukraina (Ukraine), a name first documented in the Kievan Chronicle under the year 1187. The terms Ukrainiany (first recorded in the Galician–Volhynian Chronicle under the year 1268), Ukrainnyky, and even narod ukrainskyi (the Ukrainian people) were used sporadically before Ukraintsi attained currency under the influence of the writings of Ukrainian activists in Russian-ruled Ukraine in the 19th century. From the 14th to the 16th centuries, the western portions of the European part of what is now known as Russia, plus the territories of northern Ukraine and Belarus (Ruthenia), were largely known as Rus, continuing the tradition of Kievan Rus'. People of these territories were usually called Rus or Rusyns (known as Ruthenians in Western and Central Europe).

The Ukrainian language is, like modern Russian and Belarusian, a descendent of Old East Slavic. In Western and Central Europe it was known by the exonym "Ruthenian". In the 16th and 17th centuries, with the establishment of the Zaporozhian Sich, names of Ukraine and Ukrainian began to be used in Sloboda Ukraine. After the decline of the Zaporozhian Sich and the establishment of Imperial Russian hegemony in Left Bank Ukraine, Ukrainians became more widely known by Russians as "Little Russians", with the majority of Ukrainian elites espousing Little Russian identity and adopting the Russian language, as Ukrainian was outlawed in almost all contexts.

This exonym—regarded now as a humiliating imperialist imposition—did not spread widely among the peasantry, which constituted the majority of the population. Ukrainian peasants still referred to their country as "Ukraine" (a name associated with the Zaporozhian Sich, with the Hetmanate and with their struggle against Poles, Russians, Turks and Crimean Tatars) and to themselves and their language as Ruthenians/Ruthenian.^{[need quotation to verify]}

With the publication of Ivan Kotliarevsky's Eneyida (Aeneid) in 1798, which established the modern Ukrainian language, and with the subsequent Romantic revival of national traditions and culture, the ethnonym Ukrainians and the notion of a Ukrainian language came into more prominence at the beginning of the 19th century and gradually replaced the words "Rusyns" and "Ruthenian(s)". In areas outside the control of the Russian/Soviet state until the mid-20th century (Western Ukraine), Ukrainians were known by their pre-existing names for much longer. The appellation Ukrainians initially came into common usage in Central Ukraine and did not take hold in Galicia and Bukovina until the latter part of the 19th century, in Transcarpathia not until the 1930s, and in the Prešov Region not until the late 1940s.

The modern name Ukraintsi (Ukrainians) derives from Ukraina (Ukraine), a name first documented in 1187. Several scientific theories attempt to explain the etymology of the term. According to the traditional theory, it derives from the Proto-Slavic root *kraj-, which has two meanings—one being the homeland as in "nash rodnoi kraj" (our homeland), and the other being "edge, border"—and originally had the sense of "periphery", "borderland" or "frontier region". According to another theory, the term ukraina should be distinguished from the term okraina: whereas the latter term means "borderland", the former has the meaning of "cut-off piece of land", thus acquiring the connotation of "our land", "land allotted to us".