evidence: Donbas is predominantly Russian-speaking and after Russia seized Crimea in 2014, its proxy forces captured more than a third of Ukraine's east in a war that never came to an end. [...] As Russia's failure to capture Kyiv became clear, it switched attention to "achieving the main goal - the liberation of Donbas". [...] "This is a big territory to control, and I think we shouldn't underestimate the geographical complexities of this," says Tracey German, professor in conflict and security at King's College London.