This inquiry leads students through an investigation of the causes of the Cold War by examining events through the perspective of both the Soviet Union and the United States. By investigating the compelling question “Who’s to blame for the Cold War?” students evaluate these events in consideration of the historiography, using the work of several preeminent Cold War historians, and the consequences of assigning blame to either country. The formative performance tasks build on knowledge and skills through the course of the inquiry and help students recognize different perspectives in order to better understand the ways in which mutual concerns and fears culminated in global tensions. Students create an evidence-based argument about whether anyone should be assigned blame in starting the Cold War after considering the tensions that emerged during and after World War II, perception of the actions taken by the United States and Soviet Union, assessing historiographical viewpoints, and considering how assigning blame affects perceptions of the actions of others.