Before the Mongols: A Patchwork of Broken Roads and Forgotten Posts

Pietro Grimaldi dumped the remaining sack of saffron onto the dusty ground of the Baghdad bazaar in 1250, his fingers trembling. Three months earlier, he had left Alexandria with a full cart of spices, a letter to his business partner Giovanni in Dadu (Khanbaliq), and a head full of plans to expand their Venetian glass trade into the Yuan court. The letter, scribbled with notes of upcoming shipments and price projections, had vanished somewhere between the Seljuk warlord’s toll checkpoint outside Hamadan and the Khwarazmian raiders’ ambush near Samarkand. His Persian translator, a wizened man from Khorasan who had walked the Silk Road for 30 years, sat cross-legged nearby blowing smoke from his water pipe. “I have never seen a caravan go from west to east without being robbed at least twice,” he said, not unkindly. “And if you are carrying a letter? It will be lost before you reach the Oxus River.”

Pietro’s story was not an outlier. For any traveler, merchant, or envoy in the 12th century, the dream of sending a message from Venice to Beijing in less than three years was a fantasy, and the odds of that message arriving at all were less than one in five. Long before the first Mongol horseman thundered out of the Mongolian steppe, Eurasian rulers had tried and failed repeatedly to build cross-continental communication networks. Their efforts were ambitious, even revolutionary for their time, but all of them eventually collapsed, leaving medieval Eurasia split into isolated, warring fiefdoms where a single message could take years to traverse a few hundred kilometers, if it survived bandits, border guards, and arbitrary tolls at all. To understand

To understand why the Mongol Yam network felt like a miracle to people like Pietro, we have to rewind 2,500 years, to the first time a ruler tried to stitch together a cross-continental communication web across Eurasia. That ruler was Darius I, the Persian king who ruled from 522 to 486 BCE, and his creation was the Royal Road, a 2,700-kilometer paved highway that stretched from his capital at Susa (in modern-day Iran) to the Aegean port of Sardis (in modern-day Turkey). On paper, it was a masterpiece of ancient engineering: Darius lined the route with 111 state-run waystations, each stocked with fresh horses, food, and lodging for official couriers, and he even planted rows of shade trees along the most desert stretches to keep his messengers from baking in the 40°C summer heat. The official couriers, called angarium, were trained to ride in shifts, passing messages hand to hand like a 5th-century BCE relay race. Ancient Greek historian Herodotus, who traveled the road a century after it was built, wrote in awe that “there is nothing in the world that travels faster than these Persian couriers,” claiming a message could make the full 2,700-kilometer trip in just 7 days. For context, that is an average speed of more than 380 kilometers per day—faster than the Pony Express would manage 2,500 years later.

But Herodotus’s praise was only half the story. The Royal Road was built for one purpose: to let Darius move his army and send royal orders across his empire as fast as possible. It was not a public highway, and it was certainly not open to merchants or private travelers. If you were a Babylonian spice merchant trying to send a letter to your cousin in Ephesus, you could not use the Royal Road’s waystations, nor could you tap into its courier network. You would have to join a random caravan traveling the same route, pay exorbitant tolls to local Persian satraps (provincial governors), and hope you did not run into the bandits that infested the remote mountain passes between Media and Cappadocia. And if the Persian Empire collapsed? The Royal Road would vanish with it. Sure enough, when Alexander the Great conquered Persia in 330 BCE, he did use the Royal Road for his own couriers at first, but after his death in 323 BCE, his empire split into four warring Hellenistic kingdoms, and the waystations fell into disrepair. By 200 BCE, large stretches of the road were overgrown with weeds, the shade trees had been cut down for firewood, and the angarium system had been completely abandoned. A message that could have crossed the empire in 7 days in 500 BCE would take 3 months to travel the same route 300 years later, if it arrived at all.

The Romans, always eager to one-up their Persian rivals, built their own version of the Royal Road 200 years later: the cursus publicus, the world’s first state-run, cross-continental postal system. Established by Augustus in 20 BCE, the cursus publicus covered more than 80,000 kilometers of paved Roman roads across Europe, North Africa, and the Near East, with more than 1,000 official waystations spaced every 10 to 15 kilometers. It had two tiers of service: the slow, cheap cursus clabellarius, for routine government mail, and the premium cursus velox, for urgent royal decrees and military dispatches, which could hit speeds of up to 80 kilometers a day using relay horses. For the first time in history, a private citizen could (if they had enough money) pay to send a letter across an empire, and the cursus publicus had standardized seals and receipt systems to prove the letter had been sent and received. In 9 CE, for example, the Roman general Germanicus sent a dispatch from the Germanic frontier to Rome announcing his victory over the rebel leader Arminius: the message traveled more than 2,000 kilometers in just 12 days, a speed that would not be matched in Europe again for another 1,500 years.

But like the Royal Road, the cursus publicus was a product of a single, centralized state, and it collapsed the moment that state fell apart. By the 3rd century CE, the Roman Empire was wracked by civil wars, barbarian invasions, and economic collapse. The government could no longer afford to maintain the 1,000+ waystations, so it started shutting them down one by one. By the time the Western Roman Empire fell in 476 CE, 90% of the cursus publicus network in Western Europe had been abandoned. The paved Roman roads remained, of course, but without waystations, fresh horses, or armed guards, they were useless for long-distance communication. A letter sent from Rome to Londinium (London) in 400 CE would take 10 days via the cursus publicus; by 600 CE, the same trip would take 3 months, and the traveler would have to fend off Anglo-Saxon raiders, Frankish warlords, and random toll collectors every 20 kilometers. In the Eastern Roman (Byzantine) Empire, the cursus publicus limped along for another 500 years, but it only covered the Balkans and Anatolia, and it was constantly disrupted by wars with the Persians, Arabs, and later the Turks. By 1000 CE, the cursus publicus was a shadow of its former self, and cross-continental communication between Europe and Asia was completely impossible via official channels.

Meanwhile, on the other side of Eurasia, the Han Dynasty of China had built its own equally impressive postal system, the yìzhàn (驿站) network, which covered more than 10,000 kilometers of roads across the empire, from the Korean peninsula to the Ferghana Valley in Central Asia. Like the Romans and Persians, the Han built waystations every 30 li (roughly 15 kilometers) where couriers could swap horses, rest, and get food, and they had a formal legal code, the *Yìzhàn Lìng* (Postal Regulations), that laid out strict penalties for delays: a courier who was even one day late would be beaten 20 times with a bamboo stick, and if a letter was lost, the courier could be executed. During the height of the Han Dynasty in the 1st century CE, a message could travel from the capital Chang’an (modern Xi’an) to the westernmost outpost of Dunhuang, more than 4,000 kilometers away, in just 10 days—a speed that would not be matched in China again until the Mongol era.

But the Han postal system, like its Persian and Roman counterparts, was built for a single empire, and it collapsed the moment that