Gregory Aldrete: The Roman Empire - Rise and Fall of Ancient Rome | Lex Fridman Podcast #443

Historian Gregory Aldrete explains Rome’s rise through limitless manpower and cultural absorption, and traces its fall to succession failures, plague, and severed food supply.

• Rome’s early military edge was not tactics or technology but near-unlimited manpower from incorporating conquered Italians as half-citizens or allies required to supply troops.
• At Cannae (216 BC), Hannibal’s double-envelopment killed ~60,000 Romans in one afternoon — more than US deaths in all Vietnam War years.
• Augustus’s single greatest failure was leaving no succession mechanism; hereditary selection produced Caligula and Nero, adoption of competent adults produced the Five Good Emperors.
• The linen-and-glue linothorax armor worn by Alexander the Great offered protection equivalent to 2mm bronze at roughly half the weight (~11 lb vs 24–26 lb).
• Rome’s population collapse in the 5th century AD was triggered largely by Vandal conquest of North Africa and Spain, severing the grain supply to the city.
• Afghanistan has defeated every major invader from Alexander through the Americans by the same two errors: ignoring mountainous terrain and misreading tribal versus centralized loyalty.
• Julius Caesar’s Julian calendar — 365 days, 12 months, leap years — remains essentially our calendar today; Pope Gregory made only a minor correction.

Guests: Gregory Aldrete, historian specializing in ancient Rome and military history, University of Wisconsin–Green Bay · 2024-09-12 · Watch on YouTube