The Roman Empire did not fall in 476 CE. Only the western half did. The eastern half ruled from Constantinople for another thousand years, outlasting the Western collapse by longer than the entire United States has existed. The empire we forgot was the more durable one.
For three centuries, historians blamed barbarians, Christianity, and moral decay. Modern scholarship tells a far more interesting story — one about climate, disease, complexity, and a crisis that began long before anyone noticed.
