Si Sheppard – How did a few hundred Spanish soldiers topple two empires?

Dwarkesh opens with the plain facts, because the plain facts are the strange part. A few hundred conquistadors arrive on a continent they know nothing about and, within a matter of years, subjugate empires of millions. They win battles outnumbered a hundred to one, sometimes a thousand to one, and in many cases without taking a single casualty. And they do it while upwards of 99% of their fighting forces are made up of the very natives they are about to subjugate.

The frame he puts around it is deliberately contemporary. AI takeover is filed away as science fiction, but this would not be the first time an alien force, with motivations the natives do not understand, used diplomatic cunning and technological advantage to outmaneuver and then take over a much larger and well-established order. That is the reason for the episode; the history is the substance.

So the first question is the plain one: what did Cortés actually do, what did Pizarro do, and how did these conquests go down?

Sheppard starts a century earlier, because the conquest is a by-product of a commercial problem. This is the birth of the modern world, played out five to six hundred years ago, and it created the globalized community everyone now lives in.

In the fifteenth century Europe was backed against the wall of the Atlantic, under pressure from outside forces and cut off from the economic core of the East — the spice and silk that had driven the Eurasian economy. Being cut off forced innovation. Prince Henry the Navigator turns the Atlantic from a barrier into a superhighway, and the mechanism is knowledge: captains report back on tides, winds and whatever coast they managed to reconnoiter, the map is built out generation by generation, and eventually there is a route around the southern tip of Africa straight to India that cuts out the middleman.

Spain goes west instead. Columbus in 1492 was an entrepreneur running an expedition to reach the Oriental markets by sailing the other way, and his figures were completely wrong. He was saved by an entire continent sitting where he expected Japan, China and the Spice Islands. The irony is that this was initially received as a disappointment — and only over time became visible as potential in land, in wealth and in people.

The hinge is 1511, when an ambitious nobleman, de Velázquez, seizes Cuba and uses it as a base for expeditions along the coast of Mesoamerica. In 1518 he assigns that task to Hernán Cortés, with whom he has had a tempestuous relationship. Cortés had arrived in 1511, had some legal training, served as a notary and worked up to alcalde — chief magistrate — of Cuba. He wanted considerably more than that.

He takes the governor's warrant and runs past it, recruiting men for a much wider goal: not to explore the coast but to penetrate the interior, find out what is there, and seize it. When Velázquez realizes what is happening he tries to stop him, and there is a scene on 18 November 1518 at the waterfront — the governor calling out, Cortés assuring him that everything is under control as he gets into the boat. By then control had already changed hands. It was Cortés's expedition.

He is, literally, going off the side of the map into terra incognita. What he has instead of knowledge is political antennae, honed in the islands, and they tell him early that there is a significant imperial power with hegemony on the mainland, and that its subject peoples chafe under it.

He lands among the Totonacs, recently incorporated into the orbit of a people who called themselves the Mexica — hence Mexico — and who came down to history, from their mythical homeland of Aztlán, as the Aztecs. The Totonacs resented that authority the way subjugated peoples do, and saw the outsiders as a chance to throw it off.

With that relationship established he marches inland into Tlaxcalan territory, and the Tlaxcalans respond like an immune system: they rally to expel him. What follows is the first surprise. He fights them to a standstill for long enough that they arrive at a new arrangement — they register his strength and his potential, swing to his side, and from then on serve as guides and reinforcements for the march inward.

Dwarkesh stops here for the numbers, because they reframe the achievement: a few hundred on Cortés's side against multiple thousands of Tlaxcalans, and he is fighting without native support. Even the standstill is remarkable. This is where the Old World/New World differentials start to bite, and the text Sheppard credits for getting him into the subject is Jared Diamond's Guns, Germs, and Steel, whose title is the list.

The guns, in reality, were not the significant item. Once the shock wore off, the natives worked out that reload times made firearms a limited battlefield asset. Steel was the critical one. Local weapons were wood, stone and obsidian — volcanic glass, razor sharp when honed, genuinely dangerous as a slashing weapon — but against steel armour, and especially steel helmets, much less effective.

The conquistadors also brought a doctrine. Long Toledo steel blades used as thrusting weapons, against opponents whose cut-and-slash technique opens the side of the body early, plus generations of inherited military training: technology and skill compounding into an edge that is not reducible to either.

They were not invincible, and Cortés knew it. He was taking casualties and was careful to bury his dead underneath the houses they were sheltering in, so the Tlaxcalans would not learn that they were having any success in hand-to-hand combat. It was as much a mind game as a physical one.

The decisive weapon was the horse, and Sheppard is emphatic about it. Sail power got them anywhere on the coast; the interior was a different problem, and the horse solved it. There were no native equivalents — the horse originated in North America and had died out there — and more broadly no beast of burden at all, integrated into neither the economy, nor daily life, nor the military.

The Inca had the llama, and their armies trailed miles of pack animals; the Aztecs had nothing comparable. Their only domestic animals were the turkey and the Chihuahua.

Add the war mastiffs — armoured fighting dogs trained to take down men — and the psychological impact compounds. But the horse is the operational asset: on attack it breaks any formation without the weapons, training or discipline to stand against massed shock cavalry, and when things go badly it lets the Spaniards disengage faster than anyone can pursue.

The Tlaxcalans are not naive about any of this. They are the last major entity in Mesoamerica still able to go toe-to-toe with the Aztecs, they have been surrounded, and the ceremonial flower wars have been escalating into something more obviously like conquest. They have been cut off from the coast and from salt. This is a Hail Mary: ally with a handful of strangers and there may be a way out of a strategic trap that is closing.

So they march with him to Tenochtitlan — the capital on Lake Texcoco, the glittering jewel of the Aztec Empire — and the two worlds meet when Cortés comes down the causeways and meets Moctezuma II, the huey tlatoani, the Great Speaker. The interface between them is a single person: Doña Marina, Malinche, translating from one side to the other. Sheppard calls the dialogue that follows one of the great tipping points in history.

Moctezuma was not surprised. It is his empire, he has envoys, emissaries, scouts and spies everywhere, and what they report is that something has washed up on the shores of the empire and is determined to meet him.

His first move is to bargain and to send Cortés away with precious gifts — which has the opposite effect, because once Cortés has held Aztec gold he is determined to go to the centre. His council urges him not to let Cortés proceed, and his own brother Cuitláhuac tells him plainly that if he lets this man into his house, the man will take the house. Moctezuma proceeds anyway, and generations of historians have condemned him for it.

Sheppard thinks it was his best option, whether or not he knew it. Better to have Cortés as a guest inside Tenochtitlan than loose in the empire talking to subject peoples and inflaming them against central authority. He may also have believed the story: an envoy from a great emperor across the ocean. Cortés had no warrant to claim any such thing and told anyone who would listen that he spoke for Charles V, Holy Roman Emperor — who had no idea who Hernán Cortés was. It was improvisation at an extraordinary level, and for a moment it produced stasis.

The stasis breaks from the coast. Word arrives that an Aztec regional officer, on his own initiative, has moved against the Spaniards left behind with the Totonacs and killed some of them. Cortés takes it as a pretext, walks into Moctezuma's palace and informs him that for his own safety he is now in Spanish protective custody and should come along, or there will be violence.