Ukraine and Russia are today at opposite points of the political spectrum: Despite 300 years of contact with Russian authoritarian politics, Ukraine's post-independence period has been characterised by pluralism. To explain why and how Ukraine's and Russia's paths diverged, this monograph investigates the century-long and Soviet origins of regionalism in Ukraine, which the author argues are at the foundation of the modern Ukrainian institutional system. Drawing on unused archival material, the book re-examines the relationship between Moscow, Kyiv, and the Ukrainian regions in the period from spring 1917 to summer 1994 to demonstrate how interlinked political and economic incentives and constraints determined the opportunities and institutional interests of both the Ukrainian leadership and those of the Ukrainian regions, and how this institutional framework affected in turn the dynamic of the relationship between the central leadership in Moscow, the Ukrainian leadership, and the regions. The result - weak central authority and pronounced regionalism - was Ukraine's Soviet legacy, and the established power of regional clans made (post-Soviet) Ukrainian politics resistant to Russian?style authoritarianism, even when the Soviet centralised party-state system collapsed. This innovative and wide-ranging approach to the history of economic management highlights the importance of considering long-term historical trends for understanding both the complicated nature of Soviet institutions and their varied and contested legacies across post-Soviet space.