Timothy Snyder, Richard C. Levin Professor of History at Yale, continues his course on the making of modern Ukraine by tracing how the early modern Polish state shaped the lands that became Ukraine. He covers the expansion of Polish noble power into Ukrainian territory, the resulting social and religious tensions between Polish landlords, Ukrainian peasants, and Cossacks, and the Cossack uprisings that followed. Snyder connects these events to larger questions running through the course: what makes a nation exist, how Polish, Jewish, and Russian self-understanding is bound up with Ukrainian history, and how the Cossack revolt fits into the longer story of Ukrainian statehood. The lecture is part of a Yale course available with Ukrainian and Russian subtitles, and situates the seventeenth century Cossack revolution as a turning point in the region's political development, showing how resistance to Polish rule laid groundwork for later Ukrainian identity.