Putin’s assault on Ukraine triggered an energy crisis that sent Europe’s economies into a tailspin and put the European energy transition to the test. But how did the European Union, a leader in climate action, become so dependent on Russian oil and gas to begin with?  This season, we look at the energy systems of Germany and Poland. Both have very different energy systems, but both became dependent on Russian energy for heating homes, firing power plants, and fueling businesses. In this episode, we look at the immediate impact of the Ukraine invasion on that dependency and the historical influences behind it – from Germany’s pursuit of natural gas to Poland’s centuries -long relationship with coal. Then we ask whether Europe's initial response to the crisis– leaning more heavily on fossil fuels – will accelerate or slow down the region's push toward green energy.