In April last year, as shells crashed down on the besieged Ukrainian city of Mariupol, British national Aiden Aslin surrendered to the advancing Russian forces. Surrounded on all sides and holed up in the tunnels under the colossal Azovstal steel plant, hundreds of Ukrainian soldiers who had signed up to defend their country would begrudgingly lay down their arms over the weeks that followed.

Those captured during the three-month siege faced brutal treatment at the hands of the Russians, with malnutrition, beatings and a lack of medical care. One Ukrainian marine, Mykhailo Dianov, was barely recognisable when a prisoner exchange was eventually brokered – emaciated and with his broken arm set at an excruciating angle. Aslin’s case was a little different. Despite holding dual Ukrainian and British citizenship and having signed up for a contract with the country’s armed forces just like his brothers in arms, he was branded a foreign mercenary and sentenced to death by a kangaroo court operated by Moscow’s proxies in Donetsk. Only a deal brokered by the Saudi Arabian government spared his life and saw him return home.

Convinced of their superiority to Kyiv’s defenders, the idea that soldiers of fortune from overseas are turning the tide of the war has become a national obsession in Russia. “Precision strikes eliminated 130 foreign mercenaries,” a Defence Ministry official claimed just last week in yet another unevidenced missive. According to Foreign Ministry Spokeswoman Maria Zakharova, more than 3,000 fighters from the UK, US, Poland and Canada have been killed in the hostilities so far “despite the fact that in most countries mercenary work is banned by law.”

And yet, all the while claiming to be fighting a shadowy army of paid-to-fight soldiers, Russia has itself become entirely dependent on the notorious Wagner Group, a private military company with a record of human rights abuses from Africa to Eastern Europe. While the firm was once shrouded in secrecy, the Ukraine war has given it a marketing opportunity like no other – going as far as opening a glass-and-steel headquarters in St. Petersburg.

Yevgeny Prigozhin, an oligarch, convicted fraudster and close confidante of Russian President Vladimir Putin, has long been believed to be the man behind the mercenary outfit. But prior to the invasion in February, the catering company magnate would sue for defamation anyone who so much as suggested he was involved with the Wagner Group – which had at the time been running operations in Syria, Libya and the Central African Republic. Now, Prigozhin regularly appears in recruiting videos, touring prisons across the country to sign up desperate men to send to the front lines.

In one clip shot on Prigozhin’s mobile phone, he interviews one of his employees who has been deployed to the apocalyptic battlefront near the city of Bakhmut. In broken Russian, the camouflage-clad man explains he is from Cote d’Ivoire and had been serving time in a prison colony before being let out to become a stormtrooper. “Don’t tell them what you were in jail for,” the oligarch laughs, “the only question is how well you fight.”

In December, the White House warned that the Wagner Group was looking to escalate the conflict, having bought weaponry from North Korea and shipped it to Ukraine. Rockets and missiles were said to have been included in the shipments. Now, US lawmakers are considering designating it a terrorist organisation, and eyeing its global influence in places like the Middle East and North Africa.

However, Prigozhin’s outfit may well pose a threat in an unexpected country – Russia itself. The emboldened mercenary gang master has already shown he is unafraid of using his newfound value to publicly criticise Moscow’s top brass, having accused generals of failing in their duties and making mistakes in Ukraine.

In one well-covered spat, Prigozhin backed a soldier who described the army Chief of Staff as a “motherfucker” in an expletive-laden video rant, accusing the Kremlin of giving conscripts inadequate weapons and equipment. “We are fighting against the entire Ukrainian army near Bakhmut. Where are you? It’s about time you help us,” the soldier said. “When you’re sitting in a warm office, it’s hard to hear the problems on the frontline,” Priogzhin explained.

On Monday, he hit out at Defence Ministry claims that the army was leading an offensive on Soledar, a salt mine town where they have made advances. “I’d like to stress that Soledar is being taken solely by Wagner units,” he wrote in a statement on Telegram. The pyrrhic victory is a rare success story for the country’s catastrophic war effort, and Priogzhin is clearly wasting no time in taking credit for it.

And yet, it’s not the training or the equipment that Wagner gives its troops that seems to be making a difference, but its ability to levy large numbers of inmates, debtors and other vulnerable people, and its willingness to march them into machine gun fire. According to a US official who spoke to The Guardian last week, out of 50,000 mercenaries recruited by the military company, more than 4,100 have been killed in action and a further 10,000 wounded. Over 1,000 were killed between late November and early December near Bakhmut alone.

According to Mikhail Khodorkovsky, a former oligarch hounded out of Putin’s Russia for his political activism, Wagner bosses now have as much power as Kremlin insiders and even top government ministers. “They are engaged in terrorism and killing,” he told the UK Parliament’s Foreign Affairs Committee in November, urging Western nations to take action against its finances and operations.

With its conventional forces weighed down by corruption and incompetence, Wagner is evidently on the rise, pitching itself as a slicker, more effective alternative. So too is the personal phalanx of fighters commanded by Chechen despot and Putin loyalist Ramzan Kadyrov, which has long operated outside of Moscow’s control in Ukraine. While analysts say the so-called Kadyrovtsi have struggled to make an impact on the battlefield, preferring taking selfies to launching attacks, they are famed for their brutality and their ability to sow terror into civilian populations.

As the Kremlin’s war falters, the private armies it has given rise to are becoming stronger and more unpredictable than ever before. And, if Putin’s days in office are eventually brought down by the disaster he himself created, there’s every chance they could end up fighting for control not of Ukraine, but of Russia.

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