Abstract: "Russia and Ukraine: Entangled Histories, Divergent States" (Polity Press 2024) explains how over the last thirty years Russia and Ukraine diverged politically ending up on a catastrophic collision course. Russia slid back into authoritarianism and imperialism, while Ukraine consolidated a competitive political system and pro-European identity. As Ukraine built a democratic nation-state, Russia refused to accept it and came to see it as an “anti-Russia” project. After political pressure and economic levers proved ineffective and even counterproductive, Putin went to war to force Ukraine back into the fold of the “Russian world.” Ukraine resisted, determined to pursue European integration as a sovereign state. These irreconcilable goals, rather than geopolitical wrangling between Russia and the West over NATO expansion, are essential to understanding Russia’s war on Ukraine.