Cossacks in the context of Cossack uprisings

Between 1441 and 1774, the Crimean Khanate and the Nogai Horde conducted slave raids throughout lands primarily controlled by Russia and Poland–Lithuania. Concentrated in Eastern Europe, but also stretching to the Caucasus and parts of Central Europe, these raids were often supported by the Ottoman Empire and involved the transportation of European men, women, and children to the Muslim world, where they were put on the market and sold as part of the Crimean slave trade and the Ottoman slave trade. The regular abductions of people over the course of numerous incursions by the Crimeans and the Nogais greatly drained Eastern Europe's human and economic resources, consequently playing an important role in the emergence of the semi-militarized Cossacks, who organized retaliatory campaigns against the raiders and their Ottoman backers.

Trading posts in Crimea had previously been established by the Genoese and the Venetians to facilitate earlier Western European slave routes. The Crimean–Nogai raids largely targeted the "Wild Fields" of the Pontic–Caspian steppe, which extends about 800 kilometres (500 mi) north of the Black Sea and which now contains the majority of the combined population of southeastern Ukraine and southwestern Russia.

The Pereiaslav Agreement or Pereyaslav Agreement (Ukrainian: Переяславська рада, romanized: Pereiaslavska Rada, lit. 'Pereiaslav Council', Russian: Переяславская рада) was an official meeting that convened for a ceremonial pledge of allegiance by Zaporozhian Cossacks to Russian tsar Alexis (r. 1645–1676) in the town of Pereiaslav in central Ukraine, in January 1654. The ceremony took place concurrently with ongoing negotiations that started on the initiative of Hetman Bohdan Khmelnytsky to address the issue of the Cossack Hetmanate with the ongoing Khmelnytsky Uprising against the Polish–Lithuanian Commonwealth and which concluded the Treaty of Pereiaslav (also known as the March Articles). The treaty itself was finalized in Moscow in April 1654 (in March according to the Julian calendar).

Khmelnytsky secured the military protection of the Tsardom of Russia in exchange for allegiance to the tsar. An oath of allegiance to the Russian monarch from the leadership of the Cossack Hetmanate was taken, shortly thereafter followed by other officials, the clergy and the inhabitants of the Hetmanate swearing allegiance. The exact nature of the relationship stipulated by the agreement between the Hetmanate and Russia is a matter of scholarly controversy. The council of Pereiaslav was followed by an exchange of official documents: the March Articles (from the Cossack Hetmanate) and the tsar's declaration (from Russia).

Kharkiv is the second-largest city in Ukraine. Located in the northeast of the country, it is the largest city of the historic region of Sloboda Ukraine. Kharkiv is the administrative center of Kharkiv Oblast and Kharkiv Raion. Prior to the Russian invasion of Ukraine in early 2022, it had an estimated population of 1,421,125.

Founded in 1654 as a Cossack fortress, by late 19th century Kharkiv had developed within the Russian Empire as a major commercial and industrial center. From December 1919 to January 1934, Kharkiv was the capital of the Ukrainian Soviet Socialist Republic. During this period migration from the distressed countryside and a relaxation of restrictions on Ukrainian cultural expression changed the city's ethnic complexion: Ukrainian replaced Russian as the largest recorded nationality. It was the sixth largest city in the Soviet Union during its existence.

Dnipro is Ukraine's fourth-largest city, with about one million inhabitants. It is located in the eastern part of Ukraine, 391 km (243 mi) southeast of the Ukrainian capital Kyiv on the Dnipro River, from which it takes its name. Dnipro is the administrative centre of Dnipropetrovsk Oblast. It hosts the administration of Dnipro urban hromada. Dnipro has a population of 968,502 (2022 estimate).

Archeological evidence suggests the site of the present city was settled by Cossack communities from at least 1524. Yekaterinoslav ("glory of Catherine") was established by decree of the Russian Empress Catherine the Great in 1787 as the administrative center of Novorossiya. From the end of the 19th century, the town attracted foreign capital and an international, multi-ethnic workforce exploiting Kryvbas iron ore and Donbas coal.

The Caucasian War (Russian: Кавказская война, romanized: Kavkazskaya voyna) or the Caucasus War was a 19th-century military conflict between the Russian Empire and various peoples of the North Caucasus who resisted subjugation during the Russian conquest of the Caucasus. It consisted of a series of military actions waged by the Russian Imperial Army and Cossack settlers against the native inhabitants such as the Adyghe, Abazins, Ubykhs, Chechens, and Dagestanis as the Tsars sought to expand.

Russian control of the Georgian Military Road in the center divided the Caucasian War into the Russo-Circassian War in the west and the conquest of Chechnya and Dagestan in the east. Other territories of the Caucasus (comprising contemporary eastern Georgia, southern Dagestan, Armenia and Azerbaijan) were incorporated into the Russian Empire at various times in the 19th century as a result of Russian wars with Persia. The remaining part, western Georgia, was taken by the Russians from the Ottomans during the same period.

The Cossack raids largely developed as a reaction to the Crimean–Nogai slave raids in Eastern Europe, which began in 1441 and lasted until 1774. From c. 1492 onwards, the Cossacks (the Zaporozhian Cossacks of southern Ukraine and the Don Cossacks of southern Russia) conducted regular military offensives into the lands of the Crimean Khanate, the Nogai Horde, and the Ottoman Empire, where they would free enslaved Christians and return home with a significant amount of plunder and Muslim slaves. Unlike the Tatars, Cossack raiders were capable of capturing and devastating highly fortified cities. Though difficult to calculate, the level of devastation caused by the Cossack raids is roughly estimated to have been on par with that of the Crimean–Nogai slave raids. According to History of Ruthenians, Cossack raids during Sirko's era were a hundred times more devastating than Crimean–Nogai raids.

The Zaporozhian Cossacks or Zaporizhian Cossacks, also known as the Zaporozhian Cossack Army or the Zaporozhian Host (Ukrainian: Військо Запорозьке, romanized: Viisko Zaporozke), were Cossacks who lived beyond (that is, downstream from) the Dnieper Rapids. They were predominantly Ruthenians, but also included other ethnic groups (most notably their legendary Kosh Otaman Ivan Sirko was of Moldavian origin). Along with Registered Cossacks and Sloboda Cossacks, Zaporozhian Cossacks played an important role in the history of Ukraine and the ethnogenesis of Ukrainians.

The Zaporozhian Sich grew rapidly in the 15th century from serfs fleeing the more controlled parts of the Polish–Lithuanian Commonwealth. The least controlled region, that was located between the Dniester and mid-Volga was first known from the 15th century as the Wild Fields, which was subject to colonization by the Zaporozhian Cossacks. Zaporozhian Host became established as a well-respected political entity with a parliamentary system of government. During the course of the 16th, 17th and well into the 18th century, the Zaporozhian Cossacks were a strong political and military force that challenged the authority of the Polish–Lithuanian Commonwealth, the Tsardom of Russia, and the Crimean Khanate.

The Khmelnytsky Uprising, also known as the Cossack–Polish War, Khmelnytsky insurrection, or the National Liberation War, and Cossack Revolution, was a successful Cossack rebellion with elements of religious war that took place between 1648 and 1657 in the eastern territories of the Polish–Lithuanian Commonwealth, resulting in Cossack victory and the creation of the Cossack Hetmanate in present-day Ukraine. Under the command of Cossack Hetman Bohdan Khmelnytsky, the Zaporozhian Cossacks, allied with the local Ruthenian (Ukrainian) peasantry and initially the Crimean Tatars, fought against the Commonwealth's forces. The war was accompanied by mass atrocities committed by Cossacks against prisoners of war and the civilian population, especially Poles, Jews, Roman Catholic and Ruthenian Uniate clergy, as well as savage reprisals by the Polish szlachta and the loyalist Jeremi Wiśniowiecki, the voivode of Ruthenian descent (military governor) of the Ruthenian Voivodeship.

The uprising has a symbolic meaning in the history of Ukraine's relationship with Poland and Russia. It ended the Polish Catholic szlachta's domination over the Ukrainian Orthodox population; at the same time, it led to the eventual incorporation of eastern Ukraine into the Tsardom of Russia initiated by the 1654 Pereiaslav Agreement, whereby the Cossacks would swear allegiance to the tsar while retaining a wide degree of autonomy. The event triggered a period of political turbulence and infighting in the Hetmanate known as the Ruin. The success of the anti-Polish rebellion, along with internal conflicts in Poland and concurrent invasions waged by Russia and Sweden against the Poles, ended the Polish Golden Age and caused a secular decline of Polish power during the period known as "the Deluge".

The Russian conquest of Siberia took place during 1581–1778, when the Khanate of Sibir became a loose political structure of vassalages that were being undermined by the activities of Russian explorers. Although outnumbered, the Russians pressured the various family-based tribes into changing their loyalties and establishing distant forts from which they conducted raids. It is traditionally considered that Yermak Timofeyevich's campaign against the Siberian Khanate began in 1581. The annexation of Siberia and the Far East to Russia was resisted by local residents and took place against the backdrop of fierce battles between the indigenous peoples of Siberia and the Russian Cossacks, who often committed atrocities against indigenous Siberians. The conquest of the region was a spontaneous event organized by a group of adventurers; it is one of the early European colonial campaigns.

The union of Bessarabia with Romania was proclaimed on April 9 [O.S. March 27] 1918 by Sfatul Țării, the legislative body of the Moldavian Democratic Republic. This state had the same borders of the region of Bessarabia, which was annexed by the Russian Empire following the Treaty of Bucharest of 1812 and organized first as an Oblast (autonomous until 1828) and later as a Governorate. Under Russian rule, many of the native Tatars were expelled from parts of Bessarabia and replaced with Moldavians, Wallachians, Bulgarians, Ukrainians, Greeks, Russians, Lipovans, Cossacks, Gagauzes and other peoples, although colonization was not limited to formerly Tatar-inhabited lands. Russia also tried to integrate the region by imposing the Russian language in administration and restricting education in other languages, notably by later banning the use of Romanian in schools and print.

The beginning of World War I saw an increase in national awareness among the Bessarabians, and, following the beginning of the Russian Revolution in 1917, Bessarabia proclaimed its own parliament, the Sfatul Țării, which declared the Moldavian Democratic Republic. Following a Romanian military intervention, with the Romanian Army firmly in control of the region, the Sfatul Țării voted for independence and later proclaimed, on April 9 [O.S. March 27] 1918, its union with the Kingdom of Romania. Although the unification was made under various conditions, all of these except the promise of an agrarian reform, which was carried out, were later abandoned by a minority of the Sfatul. Later, the Romanian administration swiftly dissolved the assembly and rejected the protests of the former deputies. In the peace talks after World War I, the European powers awarded Bessarabia to Romania, although the newly formed Russian SSR, and the United States never recognized this.

In the Great Northern War (1700–1721) a coalition led by Russia successfully contested the supremacy of Sweden in Northern, Central and Eastern Europe. The initial leaders of the anti-Swedish alliance were Peter I of Russia, Frederick IV of Denmark–Norway and Augustus II the Strong of Saxony–Poland–Lithuania. Frederick IV and Augustus II were defeated by Sweden, under Charles XII, and forced out of the alliance in 1700 and 1706, respectively, but rejoined it in 1709 after the defeat of Charles XII at the Battle of Poltava. George I of Great Britain and the Electorate of Hanover joined the coalition in 1714 for Hanover and in 1717 for Britain, and Frederick William I of Brandenburg-Prussia joined it in 1715.

Charles XII led the Swedish Army. Swedish allies included Holstein-Gottorp, several Polish magnates under Stanisław I Leszczyński (1704–1710) and Cossacks under the Ukrainian Hetman Ivan Mazepa (1708–1710). The Ottoman Empire temporarily hosted Charles XII of Sweden and intervened against Peter I.

The Imperial Russian Army (Russian: Ру́сская импера́торская а́рмия, romanized: Rússkaya imperátorskaya ármiya) was the army of the Russian Empire, active from 1721 until the Russian Revolution of 1917. It was organized into a standing army and a state militia. The standing army consisted of regular troops and two forces that served on separate regulations: the Cossack troops and the Muslim troops.

A regular Russian army existed after the end of the Great Northern War in 1721. During his reign, Peter the Great accelerated the modernization of Russia's armed forces, including with a decree in 1699 that created the basis for recruiting soldiers, military regulations for the organization of the army in 1716, and creating the College of War in 1718 for the army administration. Starting in 1700 Peter began replacing the older Streltsy forces with new Western-style regiments organized on the basis of his already existing Guards regiments.

Don Cossacks (Russian: Донские казаки, romanized: Donskiye kazaki, Ukrainian: Донські козаки, romanized: Donski kozaky) or Donians (Russian: донцы, romanized: dontsy, Ukrainian: донці, romanized: dontsi), are Cossacks who settled along the middle and lower Don. Historically, they lived within the former Don Cossack Host (Russian: Донское казачье войско, romanized: Donskoe kazache voysko, Ukrainian: Головне Донське військо, romanized: Holovne Dons'ke viis'ko), which was either an independent or an autonomous democratic republic in present-day Southern Russia and parts of the Donbas region of Ukraine, from the end of the 16th century until 1918. As of 1992, by presidential decree of the Russian Federation, Cossacks can be enrolled on a special register. A number of Cossack communities have been reconstituted to further Cossack cultural traditions, including those of the Don Cossack Host.Don Cossacks have had a rich military tradition - they played an important part in the historical development of the Russian Empire and participated in most of its major wars.

Symon Vasyliovych Petliura (Ukrainian: Симон Васильович Петлюра; 22 May [O.S. 10 May] 1879 – 25 May 1926) was a Ukrainian politician and journalist. He was the Supreme Commander of the Ukrainian People's Army (UNA) and led the Ukrainian People's Republic during the Ukrainian War of Independence, a part of the wider Russian Civil War.

Petliura was born to a family of Cossack heritage in Poltava. From an early age he embraced socialism and Ukrainian nationalism, which he advocated through his highly prolific career as a journalist. After the 1917 February Revolution overthrew the Tsarist monarchy, the Ukrainian People's Republic was proclaimed and Petliura was elected head of its military. The Republic was briefly interrupted by the pro-German Ukrainian State, but in late 1918 Petliura, along with other members of the socialist Directorate of Ukraine, organised a revolt and overthrew the regime, restoring the Republic. He became the leader of the Directorate in early 1919, after the Bolsheviks invaded Ukraine and captured its capital. Facing imminent defeat, Petliura entered an alliance with Józef Piłsudski's Poland. The Polish–Soviet War concluded with Poland remaining independent and gaining some Ukrainian and Belorussian lands, while most of Ukraine remained under Soviet control, forcing Petliura into exile. He initially directed the government-in-exile from Poland, but eventually settled in Paris.

Kharkiv, also known as Kharkov, is the second-largest city in Ukraine. Located in the northeast of the country, it is the largest city of the historic region of Sloboda Ukraine. Kharkiv is the administrative center of Kharkiv Oblast and Kharkiv Raion. Prior to the Russian invasion of Ukraine in early 2022, it had an estimated population of 1,421,125.

Founded in 1654 as a Cossack fortress, by late 19th century Kharkiv had developed within the Russian Empire as a major commercial and industrial center. From December 1919 to January 1934, Kharkiv was the capital of the Ukrainian Soviet Socialist Republic. During this period migration from the distressed countryside and a relaxation of restrictions on Ukrainian cultural expression changed the city's ethnic complexion: Ukrainian replaced Russian as the largest recorded nationality. It was the sixth largest city in the Soviet Union during its existence.

The history of the Jews in Ukraine dates back over a thousand years; Jewish communities have existed in the modern territory of Ukraine from the time of the Kievan Rus' (late 9th to mid-13th century). Important Jewish religious and cultural movements, from Hasidism to Zionism, arose there. According to the World Jewish Congress, the Jewish community in Ukraine is Europe's fourth largest and the world's 11th largest.

The presence of Jews in Ukrainian territory is first mentioned in the 10th century. At times Jewish life in Ukrainian lands flourished, while at other times it faced persecution and anti-Semitic discrimination. During the Khmelnytsky Uprising between 1648 and 1657, an army of Cossacks massacred and took large numbers of Jews, Roman Catholics, and Uniate Christians into captivity. One estimate (1996) reported that 15,000-30,000 Jews were killed or taken captive, and that 300 Jewish communities were completely destroyed. More recent estimates (2014) report mortality of 3,000-6,000 people between the years 1648–1649.