CRITIQUE & REVIEW: William Rosen’s “Justinian's Flea: The First Great Plague and the End of the Roman Empire” valuable to understanding our history

William Rosen’s “Justinian's Flea: The First Great Plague and the End of the Roman Empire” is a very interesting and ambitious effort to explain how the outbreak of plague in the 6th Century was the historical pivot which turned the story of the West toward the creation of the Europe we recognize today. A sprawling narrative detailing such diverse topics as politics, military conquest, biology, architecture, religion, trade, demography, evolution and genetics, Rosen does a fair job of weaving all of these developments into a compelling story of what happened and why it might have happened to create our world.

In a nutshell, Rosen's thesis is the AD 542 outbreak of plague in the Roman Empire of Justinian (reign 527-565) and the wider world of Late Antiquity so weakened the West/Rome that it allowed for the destruction of the ancient empire of Persia and pruning of the Roman Empire by the Arabs a century later. The depopulation of Justinian's Mediterranean empire and the Sassanid Persians left them open to conquest by the Arabs who dodged the plague. Justinian's dream of a re-established Roman Empire centered on the Mediterranean Sea failed after wave after wave of plague every 15 years wiped out about half of the empire's population over the 6th Century. The corresponding weakening of military and economic strength of Rome freed the fledgling barbarian kingdoms in western Europe to establish their staying power free of Roman authority and orientation. Europe's axis of power and culture moved north to the Frankish empire that found its fruition in the reign of Charlemange and his establishment of the Holy Roman Empire.

The Roman Empire bore the brunt of Arab attacks losing its rich North African, Egyptian and Syrian provinces to the new faith of Islam. Though continuing to call themselves "Roman", the Constantinople regime became more and more Greek and within two generations of Justinian's reign, they were fighting for their very existence. The world empire of Rome had become a regional power later called the Byzantine Empire by historians. The Frank, Goth and Saxon barbarian tribes solidified into the European nation-states we see today.

The plague's depopulation also set off an agricultural revolution in Europe that set the stage for the population explosion of the High Middle Ages.

Rosen's book is a easy read though the author sometimes assumes his readers might know more than the do about all of the different subjects he discusses. For instance, the geometry of the architectural sections on the Hagia Sophia lost me. But I'm not a math guy.

Overall, this book will give the reader a good bridge in the story of the West from the Classical Age to the Middle Ages. The so-called "Dark Ages" were not so dark and deserve more study and understanding. Justinian's Flea is a good place to start for the average reader of history.