Sierra is a historian of East Europe and Russia. In her research, she analyses archival material in Ukrainian, Russian, and German, as well as spatial and architectural evidence, to understand the nature of political power in Ukraine over the last two centuries. Her dissertation explores how the Mezhyhirya reserve, the site of an ancient Cossack monastery on the outskirts of Kyiv, became a Garden of Eden for Imperial, Soviet, and post-Soviet leaders to imagine their political goals and (literally) destroy those of their predecessors. She has also conducted archival research on Siberian city planning, the Nazi Occupation of Ukraine, and the formation of the Russo-Ukrainian border. Before coming to Stanford, Sierra received her BA, summa cum laude, from Harvard University.