Shadow Empires: An Alternative Imperial History. Thomas Barfield (Princeton: Princeton University Press, 2023). Pp. 384 $35.00 hardcover. 13-digit ISBN: 9780691181639

In 1978, the Estonian political scientist, historian, and politician Rein Taagepera published the first of three quantitative history articles on the “Size and Duration of Empires.” In the first, subtitled “Systematics of Size,” Taagepera made the case for three phases in world history, based on step-changes in the land areas of the largest empires. The first phase was from 2850 BCE until 700 CE, the second from 500 BCE until 1600 CE, and the final one, 1600 CE until the present. Taagepera’s articles are foundational work. Although such quantitative approaches went somewhat out of fashion in the 1980s and 1990s, they have now returned to favor. One notable instance is the recent work of Peter Turchin, who, like Taagepera, was an exile from the Communist East. In Shadow Empires: An Alternative Imperial History, Thomas J. Barfield draws directly on the quantitative data compiled by Rein Taagepera and Peter Turchin. Like them, he is interested in formulating large-scale comparative theories about empires over the longue durée. Although he does not explicitly frame it in relation to Taagepera’s work, his main focus is Taagepera’s middle phase–between c. 500 BCE and 1600 CE–when the largest empires were often in the region of five million square kilometers in land area and had populations in perhaps the tens of millions of people.