Since Russian President Vladimir Putin announced his support for a plan to recruit fighters from abroad to join the Russian army in early 2022, foreigners have fought in Ukraine as part of Russian forces. Many of these fighters are mercenaries in the commonly understood sense of that term. That is, they are fighters who have gone, intentionally, to fight for Russia in return for significant payment. Although these fighters have often found themselves in Ukraine with little to no training and without their promised salaries, this article is not primarily concerned with them. Instead, it is interested in those fighters who arrived in Russia without knowing that they would be sent to the conflict, or who did not know that they were going to Russia at all. The article argues that such ‘forced fighters’ who are misled or tricked into taking part in an armed conflict should be given protection beyond that given to other combatants, specifically that they should be offered repatriation to their countries of origin. It argues that international humanitarian law is unable to effectively capture the position of these fighters or provide adequate protection to them. It suggests, rather, that the law on modern slavery can provide a way to understand and reconceptualise the position of these fighters—as victims of servitude and human trafficking—and that this body of law can deliver the remedy of repatriation to them.