Why Rome actually fell: plagues, slavery, & ice age — Kyle Harper

The Roman Empire’s collapse resulted from a catastrophic convergence of climate change and the Plague of Justinian, which triggered massive population decline and economic instability. While the Roman economy featured advanced financial markets and trade networks, it failed to achieve an industrial revolution due to a lack of self-sustaining technological innovation and scientific empiricism. Slavery served as a foundational, albeit brutal, institution that fueled Roman economic growth but ultimately failed to incentivize the mechanization seen in later eras. Throughout human history, the transition from foraging to sedentary farming increased infectious disease burdens, creating a persistent evolutionary struggle between human populations and microbial pathogens. These environmental and biological shocks, rather than just political or social factors, fundamentally reshaped the trajectory of human civilization, highlighting the role of contingency and unintended consequences in historical development.