Foreign fighters in the Russo-Ukrainian War

"[3] 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.'

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).

[1] The launch of the Russian invasion of Ukraine in February 2022 caused a significant increase in the number of foreign fighters in the conflict.

These have included fighters from Armenia,[10] Belarus,[11] Kazakhstan,[12] Kyrgyzstan,[13][14] and Latvia,[15] as well as from pro-Russian breakaway regions such as Abkhazia,[16] South Ossetia[17][18] and Transnistria.

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.

[41] 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.

[44] 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.

[46] 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".

[58][59] 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.

[62] 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.

In particular, the latter fight together with volunteers with a far-left political background [70] Following its 2022 offensive, US and Ukrainian intelligence have alleged that Russia has sought to hire and already deployed fighters from forces it supports in places such as Syria,[71] Libya[72] and the Central African Republic under the command of the Wagner Group private military forces.

[80] It was widely reported in October 2022 that the Wagner Group had attempted to recruit former members of the American-trained Afghan National Army Commando Corps which became defunct after the victory of the Taliban insurgency in August 2021.

[81][82][83] In June 2024, Bloomberg reported that Russia was detaining and forcing Africans on work visas to decide between deportation or fighting in the war.

Lemekani Nathan Nyirenda, a Zambian former student at the Moscow Engineering Physics Institute who had been sentenced to a nine-and-a-half year jail term, was killed while fighting for the Wagner Group in September 2022.

[90] Nemes Tarimo, a Tanzanian former student at Moscow Technological University who had previously received a seven-year jail term, was killed in similar circumstances in October 2022.

[95] Unofficially, since the launch of Russia's invasion in 2022, an estimated 1.500 Georgians are fighting for Ukraine in various Ukrainian Armed Forces units and the International Legion.

[96] Already during the War in Donbas (2014–2022), Belarusians fought alongside Ukraine, forming the Pahonia Detachment and the Tactical group "Belarus".

[99] In the beginning of the full-scale invasion, Belarusians have created a separate battalion named after Kastuś Kalinoŭski to defend Kyiv.

[99] The Kastus Kalinouski Regiment was also joined by Pavel Shurmei, a former Belarusian Olympic rower and world record holder.

[99] In June 2023, Valery Sakhashchyk, effective defence minister of the Belarusian United Transitional Cabinet (a government-in-exile opposed to the de facto government of Alexander Lukashenko) informed about the creation of the 1st separate amphibious assault company "Belarus", which is part of the 79th Air Assault Brigade.