Ukraine's population numbers approximately 37 million within government-controlled territory as of 2023, reduced from over 44 million in 2001 through sustained emigration and low birth rates. The 2001 census recorded ethnic Ukrainians at 77.8 percent of residents, ethnic Russians at 17.3 percent, with smaller populations of Belarusians, Moldovans, Crimean Tatars, Bulgarians, Hungarians, Romanians, Poles and Greeks. Ukrainian serves as the sole state language under constitutional provision, though Russian remains widely spoken particularly in eastern and southern oblasts. The Crimean Tatar language holds regional status within Crimean Tatar communities following their return from Central Asian deportation that occurred under Stalin in 1944. Religious adherence divides primarily among Orthodox denominations, with the Orthodox Church of Ukraine established in 2019 holding autocephalous status granted by the Ecumenical Patriarch of Constantinople, while the Ukrainian Orthodox Church maintained canonical ties to the Moscow Patriarchate until legislative restrictions in 2022-2023. The 2022 Russian invasion displaced over 8 million Ukrainians internally and drove more than 6 million across international borders, creating Europe's largest refugee crisis since 1945.
The territory now constituting Ukraine supported Scythian nomads from the 7th century BCE, evidenced by kurgan burial mounds across the steppe containing gold artifacts now held in Kyiv museums and the Hermitage in Saint Petersburg. Greek colonies established at Olbia, Tyras and Chersonesus Taurica from the 6th century BCE maintained Black Sea trade networks, with Chersonesus ruins visible near modern Sevastopol preserving basilica foundations and a Greek theater. Slavic tribes migrated into the region between the 5th and 7th centuries CE, merging with existing populations to form the cultural substrate from which Kyivan Rus emerged. Prince Volodymyr the Great unified territories centered on Kyiv and in 988 CE accepted Christianity from Byzantine Constantinople, baptizing his subjects in the Dnieper River at a site now marked by monuments on the Kyiv waterfront. This Christianization aligned Kyivan Rus with Byzantine cultural and religious traditions, establishing Church Slavonic as the liturgical language and introducing stone church architecture exemplified by the Desiatynna Church, whose foundations were excavated in Kyiv's Upper Town. Yaroslav the Wise ruled from 1019 to 1054, commissioning Saint Sophia Cathedral in Kyiv with its preserved 11th-century mosaics and frescoes, codifying laws in the Ruska Pravda legal code, and establishing marriage alliances that connected his family to Norwegian, French, Hungarian and Byzantine royal houses.
Mongol armies under Batu Khan sacked Kyiv in December 1240, destroying an estimated 90 percent of structures and reducing the population from approximately 50,000 to under 2,000 residents according to traveler Giovanni da Pian del Carpine who passed through in 1246. This devastation fractured Kyivan Rus political unity permanently, with western territories gradually absorbed into the Grand Duchy of Lithuania and the Kingdom of Poland through the 14th century. The 1569 Union of Lublin transferred Ukrainian lands from Lithuanian to direct Polish administration, intensifying serfdom and Catholic pressure on the Orthodox population. Dnieper Cossacks emerged as a military frontier society in the 15th and 16th centuries, establishing the Zaporizhian Sich fortress on islands below the Dnieper rapids as an autonomous military republic electing hetmans as commanders. These Cossacks accepted both Orthodox peasants fleeing serfdom and military adventurers, developing a reputation for raids against Ottoman and Crimean Tatar forces. Bohdan Khmelnytsky, a Cossack officer with prior Polish military service, launched a 1648 rebellion after Polish nobles seized his estate and assaulted his family, quickly gathering an army that defeated Polish forces at Zhovti Vody in May 1648 and Korsun in late May 1648. The resulting Cossack Hetmanate controlled central Ukrainian territory from 1648 until its abolition by Catherine II in 1764 and final elimination in 1775.
Khmelnytsky signed the Pereiaslav Agreement in January 1654 with Muscovite Tsar Alexis, accepting Russian suzerainty while retaining Hetmanate autonomy in a relationship whose terms remain historically disputed. Ukrainian and Russian historians interpret this agreement differently, with Ukrainian scholarship emphasizing contractual military alliance and Russian tradition portraying unconditional submission. The Hetmanate maintained elected hetmans, separate courts, tax collection and military organization until Russian tsars progressively restricted these privileges through the 18th century. Hetman Ivan Mazepa, who ruled from 1687 to 1709 and patronized baroque architecture including the reconstruction of Saint Sophia Cathedral and construction of numerous churches, allied with Swedish King Charles XII against Peter I in 1708, seeking to restore full Hetmanate independence. Russian forces burned Mazepa's capital at Baturyn in November 1708, massacring an estimated 6,000 to 15,000 inhabitants, and defeated the Swedish-Cossack alliance at Poltava in June 1709, after which Mazepa fled to Ottoman territory and died in September 1709. Catherine II destroyed the Zaporizhian Sich in June 1775, dispersing its Cossacks and opening the southern steppe to Russian colonization and agricultural development.
The 1772, 1793 and 1795 partitions of Poland transferred western Ukrainian territories to the Austrian Empire, creating a political division that persisted until 1939. Austrian-controlled Galicia developed distinct political and cultural patterns from Russian-ruled central and eastern Ukraine, with the Habsburg administration permitting Ukrainian language education and cultural organizations prohibited under Russian tsarist policy. The Ems Ukaz issued by Alexander II in 1876 banned Ukrainian language publications and theatrical performances, restricting cultural development in the Russian Empire while Galician Ukrainians published newspapers, operated reading rooms called narodny domy, and founded the Shevchenko Scientific Society in Lviv in 1873. Taras Shevchenko, born a serf in 1814 in Moryntsi village in Kyiv province, gained freedom in 1838 through purchase by artists in Saint Petersburg and produced poetry collections including Kobzar published in 1840 that established modern Ukrainian literary language. Russian authorities arrested Shevchenko in 1847 for membership in the Brotherhood of Saints Cyril and Methodius, a secret society advocating Slavic federation and serf emancipation, exiling him to Central Asia with specific prohibition against writing or painting until his 1857 release. He died in Saint Petersburg in March 1861, and his body was transferred to Kaniv where it rests on Chernecha Hora overlooking the Dnieper, now a pilgrimage site marked by a monument visible from the river.
Ukrainian political consciousness expanded through the 19th century despite tsarist restrictions, with the historian Mykhailo Hrushevsky publishing the ten-volume History of Ukraine-Rus between 1898 and 1936, establishing Ukrainian historical continuity from Kyivan Rus through contemporary periods. World War I brought occupation and violence to Ukrainian territories, with Russian, German, Austro-Hungarian and Ottoman forces fighting across the region. The February 1917 Russian Revolution enabled the March 1917 formation of the Ukrainian Central Rada in Kyiv, which declared Ukraine a People's Republic within a federated Russia in June 1917 and full independence in January 1918. Hrushevsky served as the Rada's president, but German occupation forces dissolved this government in April 1918, installing Hetman Pavlo Skoropadsky in a conservative regime dependent on German bayonets that collapsed with Germany's November 1918 defeat. The subsequent civil war from 1918 to 1921 saw Ukrainian territory contested by the Ukrainian People's Republic under Symon Petliura, the Russian Bolshevik Red Army, the anti-Bolshevik White Army under Anton Denikin, Polish forces, and the anarchist army led by Nestor Makhno operating from southeastern Ukraine. This warfare killed an estimated 1.5 million people through combat, pogroms, disease and famine, with Jewish communities suffering particularly severe violence from multiple armies, though the scale varied among forces.