Russia and Ukraine each released 35 detainees on Saturday in the biggest direct prisoner exchange between both countries since 2014. While Ukraine has referred to the freed individuals as "prisoners," Russian lawmakers and state-run media outlets have instead called them "detained persons."  

Since the outbreak of the conflict in eastern Ukraine, hundreds of prisoners have been exchanged between Kyiv and the separatist-controlled regions of Donetsk and Luhansk. Though fewer and fewer individuals have been recently released. The release and exchange of prisoners is one of the points agreed in the Minsk peace agreement. It stipulates that, ultimately, all prisoners on both sides must be freed.

Saturday's exchange marks a milestone towards realizing this objective. Two especially prominent figures were freed: Ukrainian filmmaker Oleg Sentsov, and Volodymyr Tsemakh — reportedly a former pro-Russian rebel commander in eastern Ukraine and a key witness to the downing of flight MH17 in 2014.

Did Tsemakh's release get Russia on board?

Years of frequently fruitless negotiations preceded the prisoner swap. Then, this summer, following the election of Ukrainian President Volodymyr Zelenskiy, negotiators achieved a breakthrough. Observers in Kyiv and Moscow said Zelenskiy's rise to power made both Ukraine and Russia willing to compromise.

Some, however, suspect that Russia's willingness to reach an agreement may have been related to the surprising arrest of Tsemakh by Ukraine's secret service deep inside rebel-held territory. 
Russian billionaire and Kremlin critic Mikhail Khodorkovsky told Russian radio station Echo of Moscow he was convinced Russia sought Tsemakh's release to undermine the MH17 court case, which is planned in the Netherlands next year. The 58-year-old Tsemakh, who had been remanded in custody in Kyiv on terrorism charges, was freed shortly before Saturday's major prisoner exchange.

Russia benefits most from exchange

Although each side each swapped 35 prisoners, this was by no means an exchange on equal terms. While Ukrainian prisoners were briefly remanded in custody ahead of their release, their Russian counterparts were reportedly held in a Ukrainian sanatorium. Some of them were even freed ahead of the prisoner exchange by courts. Of those prisoners handed over to Russia, only a dozen have Russian citizenship. The remaining individuals are Ukrainian nationals who sided with pro-Russian separatists.  

A closer look at who Russia freed reveals just how unequal this prisoner exchange actually is: among the 35 individuals released are 24 Ukrainian sailors who in November 2018 were detained by the Russian coast guard as their vessels attempted to pass through the Kerch Strait — even though the Hamburg-based International Tribunal for the Law of the Sea (ITLOS) in May ruled that these sailors would have to be freed anyway. 

Prisoners freed by Russia

The most prominent figure to be released from Russian captivity is 43-year-old Sentsov. He opposed the Russian annexation of Crimea. He had been arrested and sentenced in Russia to 20 years behind bars for terrorism. Despite calls for his release by high-ranking Western politicians and international campaigns in his support, Russia had previously refused to release Sentsov. Fellow activist Olexandr Kolchenko, who had been sentenced to 10 years in prison on similar charges, was also freed.

Ukrainian far-right activists Mykola Karpyuk and Stanislav Klykh were also among those freed by Russia. They had been sentenced to 22 and 20 years, respectively, for fighting alongside Chechen rebels in the first Chechen war during the 1990s. Prominent Russian journalist and human rights activist Zoya Svetova has reported that Klykh was tortured in Russian captivity and sustained severe psychological trauma.

Ukrainian journalist Roman Sushchenko, who was jailed in Russia for espionage, was also freed. His case was widely reported in the media, as was the case of 20-year-old Ukrainian student Pavlo Hryb, who was arrested in Belarus and jailed in Russia for allegedly promoting terrorism. Hryb was also released.

Individuals released by Ukraine

Before it became known that Tsemakh would be released, observers expected Russia to be most eager to see journalist Kyrylo Vyshynsky set free. The 52-year-old, who was born in Ukraine and now also has Russian citizenship, is the former editor-in-chief of RIA Novosti Ukraine, which is the Ukrainian branch of Russia's state-operated RIA news agency. Vyshynsky is accused of treason by Ukraine, yet has so far not gone on trial.

Only a few Russian nationals are part of the prisoner swap. Among them is Viktor Ageyev, who fought alongside separatists in eastern Ukraine and was captured in the Luhansk region. Russia's Defense Ministry has distanced itself from Ageyev, saying that no Russian forces are fighting with the separatists. Another Russian national who was part of the weekend swap participated in the 2014 Odessa clashes in support of pro-Russian separatists, according to Ukrainian authorities.

Then there are the cases of Maksim Odintsov and Alexander Baranov, two individuals with dual Russian and Ukrainian citizenship. Both served as Ukrainian servicemen but deserted to the Russian side during the Kremlin's annexation of Crimea. They were later arrested in southern Ukraine and sentenced to lengthy jail terms for desertion. 

The names of most of those freed by Ukraine were only made public after the swap. 

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