The Russo-Ukrainian war has seen foreign volunteers participate on both sides of the conflict. Most foreign fighters joined the conflict during one of two waves. The first wave happened from 2014 to 2019 during the war in Donbas and consisted of approximately 17,241 foreign fighters. The second wave is considered by researchers to have been much larger and began in 2022 after the Russian invasion of Ukraine. The invasion saw people of various nationalities enlist, with Ukraine forming a foreign legion and Russia recruiting mercenaries.
Background The Russo-Ukraine War has seen two distinct waves of foreign fighters: the 2014 wave to join Ukrainian volunteer battalions and pro-Russia separatist groups during the war in Donbas phase and the post-Russian Invasion of Ukraine wave starting in 2022.
War in the Donbas
The foreign fighter movement in 2014 was largely short-lived, with researcher Kacper Rekawek writing, "fighters arrived throughout the summer of 2014, and most of them were gone from Ukraine at some point in 2015, although some returned later, with a small group settling in Ukraine permanently." By the end of 2015, Rekawek notes, "both sides took steps to professionalise their forces and incorporate the bottom-up organised volunteer battalions into e.g. the Ukrainian National Guard or, in the case of the 'separatists,' into the 'army corps.' This effectively meant an end to foreign fighter recruitment for this conflict and very few (new) foreigners joined either side after the end of 2015."
An analysis of foreign fighters by Arkadiusz Legieć, a Senior Analyst at the Polish Institute of International Affairs, estimated that about 17,241 foreign fighters fought in Ukraine between 2014 and 2019. 3,879 of those foreign fighters supported Ukraine and joined foreign volunteer battalions. The largest group of foreign fighters in Ukraine was approximately 3,000 Russian citizen volunteers. The second-largest group consisted of approximately 300 Belarusians. The third-largest group consisted of approximately 120 Georgians. The only other country to exceed 50 foreign fighters was Croatia, with approximately 60 fighters. Other countries whose nationals supported Ukraine included Albania (15), Australia (5), Austria (35), Azerbaijan (20), Belgium (1), Bosnia and Herzegovina (5), Bulgaria (6), Canada (10), Czech Republic (5), Denmark (15), Estonia (10), Finland (15), France (15), Germany (15), Greece (2), Ireland (7), Israel (15), Italy (35), Latvia (8), Lithuania (15), Moldova (15), Kosovo (4), Netherlands (3), North Macedonia (4), Norway (10), Poland (10), Portugal (1), Romania (4), Serbia (6), Slovakia (8), Sweden (25), Turkey (30), the United Kingdom (10), and the United States (15).
Russian invasion of Ukraine The launch of the Russian invasion of Ukraine in February 2022 caused a significant increase in the number of foreign fighters in the conflict. The Ukrainian government announced the establishment of an officially-sanctioned foreign legion two days after it began, which had received alleged endorsement from some Western governments after ambiguous statements from officials. The Georgian Legion and Belarusian Kastuś Kalinoŭski Regiment are one of the largest such units on the Ukrainian side.
Russian president Vladimir Putin publicly welcomed fighters from abroad to join his forces. Most foreigners arriving to fight for Russia are enlisted in the Prizrak Brigade.
Russian side
Post-Soviet countries A significant number of foreign fighters from the former Soviet Union have fought in Russo-Ukrainian War for the pro-Russian side. These have included fighters from Armenia, Belarus, Kazakhstan, Kyrgyzstan, and Latvia, as well as from pro-Russian breakaway regions such as Abkhazia, South Ossetia, and Transnistria.
Russian Federation Prior to its open involvement in 2022, especially during the first peak of the war in Donbas between 2014 and 2015, Russia had previously tried to deny any formal intervention in Ukraine and portrayed Russian forces in the country as either part of local forces or Russian citizens voluntarily fighting in the country. These units have been referred as "little green men" by Western and Ukrainian media and as "polite people" by Russian media. The Russian government-supported private military company Wagner Group, largely composed of former Soviet, Eastern European and Syrian soldiers, is deployed in Ukraine to secure Russian interests while maintaining the deniability of formal Russian involvement.
Outside of Russian forces which have been described as volunteers or unrelated to the Russian government to maintain deniability, various Russian individuals and groups have joined separatist forces in Donbas. These have included Cossacks, the pro-Putin National Liberation Movement, the neo-Nazi Russian National Unity, the National Bolshevik Other Russia party, and left-wing activists. Non-Slavic ethnic minorities have been among the foreign fighters, including North Ossetians, Ingush, and Chechens.
Fighters from other countries Most foreign fighters from countries outside the former Soviet Union are from Europe. According to a report by Polish security expert Kacper Rękawek for the Polish Institute of International Affairs published in 2015, around a hundred Germans, a hundred Serbs, and thirty Hungarians were fighting for pro-Russian forces in Donbas.
In January 2026, Dmitry Usov, the head of the Ukrainian prisoner of war headquarters, said that 18,000 foreigners from 128 countries and territories have been recruited to serve in the Russian military, excluding North Korean troops.
Nepali and Indian foreign fighters
In December 2023, the government of Nepal revealed that six of its citizens had been killed in Ukraine fighting for Russian forces and urged Russia to stop recruiting young men from the country to fight in its army. Nepal's ambassador to Russia said that around 150-200 Nepali nationals have been fighting for Russia. In early January 2024, Nepal stopped issuing permits for its citizens to work in Russia or Ukraine after 10 of its citizens were killed fighting in Russia's army. The number of Nepalis killed in Ukraine is officially 12 but could be as high as 19.
In addition, Nepali foreign minister Narayan Prakash Saud said that as of December 2023, four Nepali men had been taken prisoner by the Ukrainian army, and about 100 were missing or injured.
A number of Indian nationals were reportedly 'duped' into fighting in Russia's army after being promised other jobs, admissions to "dubious private universities" and "free discounted visa extensions" within Russia, but were instead sent to the front lines. The identities of at least two Indian nationals expecting to work as "helpers" have been confirmed killed fighting at the front in Ukraine. In March 2024, India said it had uncovered a "major human trafficking network" which lured young men to Russia with the promise of jobs only to force them to fight in the war.
As of January 2025, 12 Indian nationals were killed and another 16 missing while fighting for Russia in Ukraine.
Chinese foreign fighters
On 29 November 2023, Chinese mercenary Zhao Rui was killed in action while fighting for the Russian military in Zaporizhzhia Oblast, becoming the first known Chinese combatant to die in the war.
On 8 April 2025, Ukrainian president Volodymyr Zelenskyy said that Ukrainian troops had captured two Chinese nationals that were fighting in the ranks of the Russian military against Ukraine. According to Zelenskyy, Ukrainian troops had clashed with six Chinese soldiers near the villages Bilohorivka and Tarasivka in Donetsk Oblast. Zelenskyy also said that there are "much more" Chinese citizens in Russian units.
Serbian foreign fighters A significant number of Serbian citizens and ethnic Serbs from neighbouring countries such as Bosnia (specifically the autonomous Republika Srpska) and Montenegro have joined to fight for pro-Russian forces in Donbas, having been described by external observers and the DPR/LPR authorities as one of the largest components of foreign fighters. Many of the Serb fighters are veterans of the Yugoslav Wars. Serbian units within the pro-Russian forces include the International Brigade, Seventh Brigade, Serbian-Hussar Regiment, Ural Unit, First Slavic Unit, Batman Unit, Rezanj Unit, and the Jovan Šević Detachment.
Historical links with Russia, pan-Slavism, and religious affinity have been regarded as a major factor in Serbs joining the pro-Russian forces, although many are mercenaries. Many of the fighters identify as Chetniks. In January 2024, Serbian DPR fighter Dejan Berich spoke of abuse of Serbian recruits with Russian paratroopers referring to the Serbs as "gypsies" and sending them on assaults with two or three magazines of ammunition, ordering them to obtain weapons in the battlefield.
Bratislav Živković, a Serbian mercenary and leader of the Chetniks, a Serbian extremist group, was killed in Ukraine in January 2025. In the war, he had organized Serbian mercenaries entering eastern Ukraine and supported the efforts of pro-Russian separatists.
Far-left volunteers Left-wing volunteers have gone to fight for the pro-Russian forces, accusing the Ukrainian government of being a "fascist state" and seeking to engage in an "anti-fascist struggle". However, these leftist volunteers have co-operated with far-right groups in Donbas. Among the initial volunteers were members of the Communist Party of Ukraine, as well as some members of trade unions and labor organizations opposed to the new government that emerged after the Euromaidan Ukrainian Revolution.
A small number of Spanish socialists travelled to Ukraine to fight for the separatists, with some explaining they were "repaying the favour" to Russia for the USSR's support to Republicans during the Spanish Civil War. They were also enlisting in solidarity with those who died in the Unions House fire. Spanish fighters established the 'Carlos Palomino International Brigade', which fought under the flag of the Second Spanish Republic. In 2015, it reportedly had less than ten members. Other examples include the 'DKO' (Volunteer Communist Unit) and the Interunit, both composed of foreign communist volunteers.
Latvian communist of Ugandan and Russian descent Beness Aijo was arrested in Donetsk in 2014 for fighting with separatist forces and the National Bolshevik Interbrigades.In Donetsk arrested Ayo Benes . News2Night. Retrieved on 1 May 2014.Extremists from the Crimea get over to Donetsk: on meeting for Yanukovych Aksenov's black "fighter" . News.pn (22 March 2014). Retrieved on 1 May 2014. A female member of the Israeli Communist Party had also reportedly gone to fight for the separatists in 2015.
Far-right volunteers Far-right foreign fighters from Europe and to a lesser extent North America have fought alongside the pro-Russian separatists in Donbas, including white nationalists, neo-Nazis, fascists, and Christian extremists. Motivations for these fighters have included the belief that they are fighting America and Western interests and that Vladimir Putin is a bulwark for traditional white European values who they must support against the decadent West.
One notable far-right group is the French organisation Continental Unity, which has been accused of recruiting far-right extremists across Europe to come and fight in Donbas. Other far-right groups include the Bulgarian nationalist Orthodox Dawn Battalion and the Hungarian nationalist Legion of Saint Istvan.