In the 1570s, the Viceroy of Peru assembled a mechanism that for two centuries bound Andean villages to the global circulation of money — and ground them down.
Francisco de Toledo arrived in Lima at the end of 1569 — no longer young, meticulous, with a reputation as an administrator rather than a conquistador. The Crown expected order from him: silver flowed from Potosí, but chaotically; revenues fluctuated, and local encomenderos governed Indigenous labor as they saw fit. Toledo spent several years traveling across the viceroyalty, personally inspecting provinces, counting the population, recording who owed what and to whom. Out of this accounting obsession came a system historians would spend another four centuries taking apart screw by screw. He did not invent new principles — he took the existing Inca practice of rotational labor service, the mita, and fitted it into a different machine. The Inca mita functioned as a community’s obligation to the state: men were sent in turns to build roads, work state fields, serve in the army. The labor was hard, but varied, and — crucially — embedded in an economy of mutual obligations, in which the state fed and clothed the workers. Toledo kept the word, but rewrote the terms of the contract.
His decrees of 1572–1573 mapped the geography of coercion with bureaucratic precision. Sixteen provinces — a vast arc from Lake Titicaca to the districts northwest of Potosí — were required to supply workers to the mine every year. The quota: roughly one-seventh of able-bodied male tributaries, around 16% of the adult male population. In absolute terms, that produced a nominal figure of some 13,500–14,000 mitayos a year. To organize recruitment, Toledo created 16 “mita captaincies,” each responsible for its own province. The gears had been cut; all that remained was to make them turn.
Potosí lies at more than four thousand meters above sea level — an extreme zone even for highland people. For communities living in lower valleys, the journey to the mine took weeks, sometimes more than a month. The mitayos did not go alone: their families traveled with them — wives, children, sometimes the elderly. They drove llamas laden with chuño (freeze-dried potatoes), grain, blankets. These caravans — hundreds of people and animals strung out along mountain trails — were an annual ritual that could not be refused. What gets me is this detail: the entire family pulled up stakes because a man could not feed himself at the mine on a mitayo’s wages, while the community could not support his family in his absence.
The key link in the chain of mobilization was the curacas — local chiefs, heirs to the precolonial aristocracy. The Spanish administration could not reach every village; it pressed the curacas, and the curacas pressed the communities. A curaca was responsible for ensuring that the required number of people set out. If there were too few — and more and more often, there were — the curaca paid out of his own pocket or from communal funds, making up the difference in cash. This was called buying out the mita, and for many curacas it meant personal ruin. A man who in Inca times had administered communal labor and mediated between the people and the state became, in the colonial system, a hostage to the quota.
Formally, the system looked humane: a mitayo worked one week, then rested for two. In practice, “rest” was a fiction. During his free weeks, the mitayo took side work in the same mine as a wage laborer — a minga. Otherwise, the arithmetic did not add up: a mitayo’s earnings for his working week went toward paying the tributo (the colonial head tax), food, and the candles for mine work, which the mitayo was required to buy himself. The rotation, designed as protection against exhaustion, in reality bound a man to the mine for the entire term of his service.
Potosí was not a forced-labor camp in the pure sense — and that makes its structure more complicated than it seems. Alongside the mitayos worked mingas — wage laborers who came for money. Mine owners paid mitayos roughly three times less than mingas, and the whole economic logic of the system lay hidden in that gap. Cheap forced labor subsidized extraction: without mitayos, many mines simply did not pay for themselves, especially once the rich surface veins were exhausted and they had to go deeper into the mountain.
In the 1550s, mitayos made up only around 10% of Potosí’s workforce — the city grew on free labor and easily accessible ore. By the end of the 16th century, after Toledo’s reforms, their share had risen to 30%. That does not mean the other 70% were free in any full sense of the word. Among the mingas were plenty of people who had fled their reductions and become forasteros — “outsiders,” no longer listed in the tax rolls of their home community, yet still without rights in their new place. Flight from the mita did not mean freedom; it meant another form of vulnerability. A person who fled a reduction lost access to communal land, to the network of mutual aid, to status. He could hire himself out at the same mine — but now without even the guarantees nominally due a mitayo.
Actual attendance almost never reached the prescribed quota. The demographic crisis of the 17th century — epidemics, flight, deaths in the mines — drained people from the system faster than the administration could update its lists. Curacas unable to assemble the required number of workers paid “Indians in silver” — the cash equivalent of the missing mitayos. Thus the mita, a labor obligation, was partially transformed into a monetary tax, drawing communities still deeper into a monetized economy for which they were not equipped.
Potosí’s silver cannot be understood without mercury. Before 1572, ore was processed by smelting in local furnaces — huayras — which Indigenous people set up on mountain slopes to catch the wind. The method worked with rich ore, but as the mines went deeper, the silver content of the rock fell, and the huayras lost their effectiveness. The technology of amalgamation — extracting silver with mercury — was introduced in Potosí with the involvement of Pedro Hernández de Velasco. Historian Peter Bakewell described in detail how this transition changed the entire economy of the mine: amalgamation made it possible to extract silver from low-grade ore, but demanded enormous quantities of mercury.
Mercury came from Huancavelica — a mine in central Peru, about a thousand kilometers northwest of Potosí. Huancavelica was Potosí’s mirror image: the same mita, the same forcibly mobilized communities, the same exhausting underground work — only here, instead of silver dust, mercury fumes killed people. The two mines were joined like the lungs and heart of a single organism: without mercury shipments, Potosí suffocated; without Potosí’s demand, Huancavelica lost its purpose. Caravans of llamas hauled clay vessels of mercury over mountain passes, and every vessel was a condition for tons of silver ore to become ringing coin.
Broadly speaking, the silver boom stood on four legs: the ore of Cerro Rico, the mercury of Huancavelica, the forced labor of the mita, and the colonial tax system that drove Indigenous people into monetary circulation. Remove any one of them — and the structure wobbles. The Crown understood this and jealously controlled every element: mercury was a royal monopoly, the mita a royal decree, and one-fifth of all silver mined — the quinto real — went to the treasury. Potosí was not a mine but a fiscal hub where transcontinental flows converged: silver was sent to Seville, spread from there across Europe, and then, via the Manila galleon, to China.
By the 17th century, the system began to bog down for reasons built into its own design. The population of the sixteen “mita” provinces was shrinking: epidemics, unbearable labor, flight. Communities from which a third or half the men had gone were still expected to meet the same quota — and the gap between paper lists and real people grew with every decade. Mass flight from the reductions (forced settlements into which Toledo herded scattered Indigenous populations for ease of control and taxation) created an entire social category — forasteros, people without a community, without land, without a place in the system. They settled in cities, on other people’s land, hired themselves out as laborers — and formally slipped free of the mita, though their lives did not become any easier for it.
What never stops surprising me is the inertia with which the system kept functioning despite its obvious collapse. Quotas were revised rarely and reluctantly. Mine owners, accustomed to cheap mitayo labor, lobbied for the preservation of the mita with a tenacity better applied elsewhere. In the 18th century, when actual attendance had fallen to a minimum, mine owners answered not by abolishing the system but by tightening it: practices of fixed tasks appeared — a man was not allowed out of the mine until he had met his quota, regardless of how many hours or days it took. At the same time, cash commutation expanded: instead of sending people, communities could pay in silver. For owners, it meant cash with which they could hire mingas; for communities, another tax on top of the tributo.
The paradoxical result: between 1740 and 1790, Potosí doubled its silver output while having fewer hands at its disposal than in the golden age of the late 16th century. Efficiency rose through harsher exploitation of fewer people, and because cash commutation allowed mine owners to manage hiring more flexibly. By that point, mitayos made up around 50% of the workforce — not because there were more of them in absolute numbers, but because there were even fewer wage laborers.
Potosí was already a large city before Toledo. By the time the viceroy turned to reform, life was already boiling at the foot of Cerro Rico: markets, churches, workshops, a mint. The reforms did not create Potosí — they extended its life. Without an organized influx of cheap labor, without amalgamation, without the mercury artery from Huancavelica, the silver boom would probably have faded decades earlier, once the surface veins ran dry. Toledo bought Potosí time — but the currency was Andean communities.
The price was distributed unevenly, and that is perhaps the bitterest thing about this story. The sixteen provinces entered into the mita register bore a burden their neighbors did not know. Communities outside the “mita” zone lived within the same colonial system, paid the same tributo, but did not lose their men to the mines. The border between a “mita” and a “non-mita” province could run through neighboring valleys, and on one side a village slowly emptied out while on the other it held on. This arbitrariness, fixed by a stroke of the pen in Lima, determined the fate of generations.
Potosí’s silver became the blood of the global economy of the 16th–18th centuries: it paid for Habsburg wars, bought Chinese silk, filled the coffers of Genoese bankers. The world monetary system was built on metal extracted by people who had never been invited there. The mita was finally abolished in the 19th century, during the wars of independence of the South American republics — but by then Cerro Rico had already been gouged so deeply that the mountain began to sink, while the communities that had fed it labor for two and a half centuries had changed beyond repair.