Original subtitles

[Narrator] The Incas,

an extraordinary civilization.

In just over 100 years,

from the 15th to the 16th century,

three all-powerful emperors

built an astonishing empire,

the biggest the Americas had ever seen.

[Expert 1, translated] The Inca state had a population

of 9 to 12 million people.

[Expert 2, translated] They were highly developed people.

[Narrator] The Incas left behind

monumental and intricate traces of their genius.

But the story of these great people

remains shrouded in mystery.

Where did the Incas' wealth come from?

[Expert 3] They found a lot of gold in temples.

[Expert 4, translated] What we see here are the marks

made by tools used to extract the ore.

[Narrator] How did the empire reach its climax?

[Expert 5, translated] The Inca era was an age of architects,

engineers, and great minds, who helped forge the empire.

[Narrator] Thanks to scientific advances

and ultra-realistic computer-generated images,

we're going to bring this lost civilization back to life.

[Expert 1] These archaeological remains

are proof of the majesty of the Inca state.

[Narrator] From its mysterious origins to its brutal fall,

this is the incredible story of the Empire of the Sun.

♪ ♪

♪ ♪

In a valley in the heart of the Peruvian mountains is Cusco,

a city with thousands of years of rich history

still scattered throughout its streets.

At its peak in the early 16th century,

this metropolis was home to over 40,000 people.

It was the nerve center of a powerful state,

founded and ruled by the Incas,

known as Tahuantinsuyu, the Empire of Four Parts.

[Alex Usca Baca, translated] Cusco was the political,

administrative, religious, and economic capital

of the whole of Tahuantinsuyu.

[Narrator] 500 years ago, the Incas created

the largest state on the South American continent

in just over a century.

From Cusco, three emperors ruled a territory

that stretched from the equatorial rain forests

to the deserts of Chile,

controlled thanks to a vast road network

of over 40,000 kilometers.

In the imperial capital,

daily life was organized around the main plaza,

where ritual ceremonies, festivals,

and trade took place.

♪ ♪

[César Itier, translated] Cusco was the central hub

where delicacies and goods from throughout the Inca empire

were gathered.

It served as a place of reception

where valuable items were consolidated

and also as a center for their redistribution.

[Narrator] Temples and palaces

overflowed with gold and silver.

And the legendary fortune of the Incas

spread beyond their borders.

[Ulla Holmquist Pachas] The legend of El Dorado,

it comes from rumors of a kingdom where gold was abundant.

[Dominika Sieczkowska] At this time,

when the Spaniards learned about the El Dorado,

they were told that there was a very wealthy country

with a lot of gold somewhere hidden in the jungle.

They wanted to find it.

[Narrator] This myth of El Dorado enticed

the Spanish conquerors to invade ancient Peru.

When they arrived in 1533, the chronicles recounted

their amazement at the wealth accumulated in Cusco.

The Spaniards were amazed by the Coricancha,

the main temple,

with its gardens dotted with golden statues

of maize and llamas, walls clad in gold plates,

and rooms filled with precious minerals.

They also discovered the finest textiles and ceramics

on the American continent.

But the only wealth they were interested in was Inca gold.

[Pachas] When we talk about the gold of the Incas,

we are referring to the gold of the Andean region.

[Narrator] Since the dawn of time,

Andean people have mastered the art of casting, molding,

and alloying precious metals.

[Francisco Garrido, translated] This is made of gold on the top

and silver on the bottom and has a soldered seam.

This is just one example of how the Incas mastered metallurgy

and influenced a long practiced Andean art across their empire.

[Narrator] How in a few decades did the empire become

one of the richest in the world?

[Baca] During the last Inca government led by Huayna Cápac,

the empire reached its peak splendor.

[Narrator] Huayna Cápac was

in power for over 30 years.

His father was the greatest

Inca conqueror, Tupac Yupanqui.

And his grandfather

was Pachacutec.

[Baca] They expanded into regions that now make up

much of the countries of South America.

[Sieczkowska] When the new king was making the power,

he had to conquer new areas, both for his family,

but also to show how strong he is.

[Narrator] Huayna Cápac was no exception

to this warrior tradition.

He began his reign and led campaigns in the north,

extending the borders of his empire.

♪ ♪

Conquered populations were forced to devote

part of their time to working for the empire,

constructing buildings, roads, and bridges,

or working in the fields.

This labor tax made the elites of Cusco rich,

but how was it made compulsory?

How could all these people be forced to work

for Huayna Cápac?

[Itier] There wasn't a police force or an omnipresent army.

It was a state that was fairly weak

and that needed to convince, beg, demand, and offer payment

in exchange for this work.

[Narrator] From the beginning,

the Inca Empire was based on a social pact.

In exchange for labor,

the state would feed the entire population.

On inheriting the immense kingdom,

Huayna Cápac's first challenge was to honor this social pact

over his expanded territory.

But between rugged valleys over 3,000 meters high,

jungle-covered mountains, and endless deserts,

living conditions were extreme.

[Feren Castillo Luján, translated] Since 4000 B.C.,

we know that all societies on the northern coast

have been affected by climate-related phenomena

such as El Niño and also by seismic phenomena

such as earthquakes.

Peru is a very seismic country.

[Narrator] On the Pacific coast is Chan Chan,

the former capital of a great kingdom

that was conquered by Huayna Cápac's father.

Here, the Chimú people were severely impacted

by the El Niño climate phenomenon,

which brought heavy rains and catastrophic flooding.

[Luján] Between 1250 and 1450,

the Chimú faced a constant climatic crisis

caused by the El Niño phenomenon.

It is very likely that the biggest event occurred in 1450

when torrential rains and mudslides flooded the palaces.

It destroyed the canals and created a food crisis.

[Narrator] Devastated by the torrential rains,

Chan Chan was later invaded by the Incas

and never regained its stronghold.

In the Andes, nature can wreak havoc.

[Luján] One of the greatest attributes of the Incas

is that, through conquest, they were able to adapt

to different environments, from the dry coast to the deserts,

from the high mountains to the salt flats.

This engineering ability made the Incas a great society.

[Narrator] How did the Incas tame these hostile landscapes

and feed over 10 million people?

♪ ♪

[Narrator] North of Cusco,

in the sacred valley of the Urubamba River,

a pivotal development was under way--

new farming techniques.

[Itier] While the various peoples

of the other Andean lands were immersed

in local conflicts during the 13th and 14th centuries,

the Incas in the Cusco region

developed irrigation agriculture,

learning to build terraces, irrigation canals,

and infrastructures that enabled them to intensify production.

They accumulated knowledge in this area.

[Narrator] On the heights of the Sacred Valley,

steep slopes are sculpted by thousands of parallel lines.

These are the Andean terraces, a spectacular demonstration

of the skills of the Inca builders.

The most majestic platforms

are those on the slopes of Machu Picchu.

Built early in the 15th century by Huayna Cápac's grandfather,

this complex of 700 terraces was an administrative hub,

a religious site, and a dynamic production center,

with a whole district dedicated to agriculture.

[Julio Córdova Valer, translated] The construction

of agricultural land is very different

from urban land with housing.

The stones here are native to the area.

They are granite, which is pretty hard.

But between the stones are permanent gaps

so that heat, wind, and water can circulate.

None of this was sealed.

[Narrator] To overcome the uneven terrain,

the builders dug into the mountain

and erected two-to-four-meter- high rows of stone walls.

Between the walls, cavities are filled with coarse pebbles,

a mixture of sand and rubble,

and a layer of fresh earth to help drain water.

To ensure the stability of buildings above,

the walls are compact, but pierced with drainage holes.

In the agricultural terraces,

the stones in the walls are spaced out

to allow the water to run off

and irrigate the lower platform.

In a volatile region,

these foundations can withstand landslides.

[Valer] We're in the jungle, and it rains a lot here.

The function of the agricultural terraces is to allow the water

to filter through and not settle.

The water flows constantly, and if there's a lot of it,

it comes out through the gaps in the stones.

[Narrator] Thanks to these terraces,

the Incas created almost five hectares

of arable land on the cliff side.

[Valer] It's a technique that the Incas perfected,

but it already existed in the Andean world.

[Narrator] Agricultural engineering was a key skill

for the Incas, but it was not their only one.

They were outstanding farmers.

The local diet was rich and varied,

evident through the various pre-Hispanic potteries

found throughout Peru.

The staple foods were quinoa and, above all, maize.

[Pachas] This product is used to produce

a drink called chicha...

[speaking Spanish]

...which is a corn beer

used as a liquid food

and which was offered to build bonds.

In the Inca era, at every ceremony and meeting,

there was always an exchange or delivery of chicha

by the heads of the authorities.

[Narrator] As well as seeds and grains,

Andean farmers also grew vegetables and tropical fruit.

[Pachas] The wide variety of crops grown

and the way in which they supplemented food supplies

shows that they had a great deal of technical knowledge.

[Narrator] To cultivate this diversity of foods

throughout the empire,

the Incas perfected their techniques,

treating the varied land as a laboratory.

Between Cusco and Machu Picchu,

at an altitude of 3,500 meters

the Moray terraces are unique.

Concentric rings form three huge amphitheaters.

With this funnel-shaped layout, the soil on the lowest level,

protected from wind, is warmer than that on the highest level.

Each offers a different microclimate.

♪ ♪

Thanks to these terraces,

the Incas were able to cultivate plant species

from across South America, even without plow animals.

Drawings from the early 17th century

show their rudimentary but effective tools.

[Itier] They even invented a new tool,

the foot spade, which, when plowing,

enabled earth to be lifted more efficiently.

This tool played a key role in the intensification

and agricultural success of the Incas.

[Narrator] With their new techniques and knowledge,

the Incas revolutionized agriculture

throughout the empire.

[Itier] Traditionally in the Andes,

there was a lunar calendar.

But the Incas invented a solar calendar,

which had the advantage of being more accurate

for agriculture and easier to use.

[Narrator] This division of the year is similar

to our modern solar calendar.

But how did they manage to pinpoint the changing months?

♪ ♪

[Sieczkowska] The Incas had very precise astronomical tools.

We suspect that in different Inca cities,

there were several observatories,

but we don't have traces of it.

So those astronomical tools that we have here in the Machu Picchu

are the best preserved and well-studied.

[Narrator] The structures of Machu Picchu

are built according to the sky.

In many buildings, the doors and windows

are precisely oriented towards the moon, Venus,

and most importantly, the sun.

In the Temple of the Sun,

two windows marked the major seasonal changes,

at the solstices in June and December.

Of all the buildings dedicated to astronomical observation,

the most fascinating and mysterious is Intihuatana.

[Alicia Fernández Flórez, translated] The Intihuatana

was used to observe the movement of the stars,

particularly the sun,

to determine the winter and summer solstices.

It measured the movement of the sun and the shadows it cast.

♪ ♪

[Narrator] On the promontory overlooking the whole city,

in the center of the plaza, sits the Intihuatana,

a sculpted rock

with a carefully carved block on top.

This carved stone is at the center

of a colossal solar calendar,

where the surrounding peaks served as reference points

for Inca scholars to track the sun

and the time of the year.

[Flórez] The Incas' entourage was made up of priests

and various members of the elites.

They were specialists dedicated to this type

of astronomical observation.

They weren't just anybody,

as this required a level of training.

[Narrator] Some researchers suspect a temple

in the lower part of Machu Picchu

housed a research and training center

for the astronomers in charge of the calendar.

[Sieczkowska] They were able to follow the calendar

both for agricultural, ritual aspect.

Everything that they had accomplished during the year

was thanks to the astronomical observations.

[Narrator] Emperor Huayna Cápac was the master of the harvest,

but he also controlled another essential element

of agriculture and daily life.

[Alexei Vranich] In an environment as volatile

as the Andes, water is both life and death.

You need it to grow things.

But also there's periods of, of El Niño, for example,

where water can destroy everything.

If you can control water,

if you can show people you control water,

you control the universe.

[Narrator] How did the Incas manage to become

masters of water, too?

♪ ♪

[Sieczkowska] There are water fountains, water channels.

There are terraces.

There are many structures that are not visible.

They are under the vegetation.

[Narrator] Archaeologist Dominika Sieczkowska recently

explored the Chachabamba site,

where only a few buildings have been excavated.

[Sieczkowska] Chachabamba is a very special place

because it was a stopping point between Cusco and Machu Picchu.

The pilgrims that were going to Machu Picchu itself

had to stop here and take role in ritual ablutions

related to the water.

[Narrator] These Inca buildings are surrounded

by two stretches of grass that descend in terraces.

The ground is hollowed out by interconnected canals

that form 14 channels.

[Sieczkowska] The water was coming from the upper part,

through the tunnel system,

and was flowing through here to this small pool.

And the Incas were taking possibly

their ritual bath here, downstairs.

[Narrator] To better see the overgrown complex,

scientists scanned the site

with a drone equipped with lidar

to peer beneath the vegetation.

[Sieczkowska] Thanks to lidar images,

I will have a digital model of the terrain,

and I will find some terraces,

some remains of the Inca presence

in the different sectors under the vegetation.

And then after processing and filtering the 3D point cloud,

we can look for the remains itself.

[Narrator] This analysis provides

a three-dimensional image of each Inca building,

enabling us to map the hydraulic system.

The water flows from the river via a main canal,

then is diverted into six secondary channels.

They pass through six fountains

before flowing on to eight basins.

This sophisticated network was calibrated to maintain

a low, constant flow for sacred bathing.

[Sieczkowska] The Incas adapt the terrain, the channels,

and everything what they found in Chachabamba,

to the exact amount of water and what they wanted.

It means they wanted originally to have very limited water flow,

and they planned and control it perfectly.

[Narrator] To control water and supply unique sites

such as Machu Picchu,

engineers designed tailor-made hydraulic networks.

[Flórez] In the initial planning

for the constructions of the Inca city of Machu Picchu,

one of the most important considerations

was providing fresh water.

They did this by means of the collection canal,

which can be seen here.

[Narrator] Drinking water was drawn

from an upstream spring in the mountains

and flowed down this 700-meter-long channel.

[Flórez] It has an average width of 15 centimeters

and a depth of 20 centimeters,

and water is channeled through it to the urban Inca city.

♪ ♪

[Narrator] In the Sacred Valley,

each Inca settlement has its own water management system,

some of which are still in operation today.

Despite its isolated position,

it was at Machu Picchu that the Incas perfected

agriculture, astronomy, and hydraulics.

[Narrator] The Inca Empire brought its knowledge

to the conquered peoples

in exchange for their collective labor.

In this way, the empire respected its social pact.

But this fundamental system of reciprocity did not stop there.

[Vranich] When they came into an area,

they completely redesigned it, they terraformed it.

Now, part of that was to teach this method to other people.

But, of course, they want to make it

much more productive for their own.

[Marcela Sepulveda, translated] The Inca conquest was really

a great system that was put in place to take possession

of everything desirable and useful to the empire.

[Narrator] But how did the Incas get their hands

on the most strategic and inaccessible resources?

This 3,000-meter-high plateau

dotted with vegetation and wildlife

is the Turi oasis.

[Sepulveda] One of the unique features

of this microenvironment in the middle of the desert

is the potential for underground water to rise to the surface.

[Narrator] Thanks to desert springs,

the Turi oasis has been occupied

for thousands of years.

Ruins of 600 scattered buildings

are the remains of a village

built long before the arrival of the Incas.

[Sepulveda] The Incas settled here

and took control by accepting gifts

of whatever the local population could provide.

[Narrator] The imperial officials first desired

camelids, the llamas and alpacas

that fed on the high-altitude pastures.

[Sepulveda] During Inca times,

there were around 10,000 to 20,000 animals

living in this area.

In the Andean region, there were no plows, no wheels,

no domesticated animals, so camelids were

the most important species to carry resources.

[Narrator] These herds are essential for transport,

as well as for wool, meat, and fertilizer.

But they are not the only source of wealth in the area.

[Garrido] The Incas took over the process

of extracting mineral deposits

and transformed them.

They introduced their own engineering

and in many cases increased production.

[Narrator] The Atacama Desert is abundant in minerals.

Huayna Cápac benefited from deposits of gold and silver,

as well as copper, a strategic mineral

used to make jewelry, tools, and weapons.

♪ ♪

In the vastness of the desert,

traces of these former mining operations are hard to spot.

But not far from Turi, above a deep canyon,

archaeologist Marcela Sepulveda has just identified a site

that reveals Inca methods.

[Sepulveda] Here we find a slightly semicircular shape,

and we can see straightaway that this group of stones

was part of a wall that has, in fact, completely collapsed.

[Narrator] These piles of stones,

almost invisible to the untrained eye,

are the remains of eight small, rudimentary houses.

[Sepulveda] We were able to excavate, and in one structure

we found that the floor was actually much lower.

The walls are no higher than 40 to 50 centimeters,

so the people lived in the basement

and probably had roofing made of skins

or other perishable elements, as no other remains were found.

[Narrator] The excavations also unearthed

numerous fragments of pottery.

[Sepulveda] This fragment corresponds to a piece of bowl,

a piece of ceramic.

It's a characteristic plate and shape

linked to Inca expansion in the region.

This shape isn't found among local populations.

[Narrator] Dating of these remains indicates

a human presence here more than 1,000 years

before the arrival of the Incas.

But this site was not a permanent settlement.

[Sepulveda] There isn't a graveyard.

There isn't much water.

You have to travel 400 meters down to fetch water.

So this site is linked to a temporary activity or practice,

and only a small number of people lived here,

and they came for very specific tasks.

[Narrator] What resources were the Incas looking for

in such a hostile place?

[Narrator] The ground still bears mysterious red marks,

a clue that leads to the base of the ravine,

to a human-carved hole in the rock.

[Sepulveda] We don't know the extent of the interior,

but we can see from the cliff base

that there are other openings

about 20 or 30 meters down the valley.

This was a very large mine

with various extraction shafts.

In fact, you can see the shapes left by the tools

used to extract the ore.

[Narrator] The ore is a mineral called hematite.

Its red pigment was sought after by the Incas

for coloring buildings and textiles.

[Sepulveda] This is one of the major colors of the Inca,

the elite and the authorities.

This color is generally associated with people

who are important in the social structure

and the organization of the Incas.

[Narrator] Once extracted, the ore was taken and crushed

near the settlement, using rocks as anvils.

[Sepulveda] Here we can see the hollowed parts

and understand the movement used to grind and obtain

this very fine powder.

The people who worked the mine

and were responsible for pigment production and grinding

were local people,

but they were still under Inca control.

[Narrator] The proof of this relationship

is hidden on a wall covered in red stains.

[Sepulveda] Thanks to image processing,

we can take photographs and see that there are many symbols.

Amongst these markings, there's a checkerboard pattern,

a shape associated with Inca expansion.

[Narrator] This outpost was linked

to 40,000 kilometers of roads

that enabled the empire's goods to flow into Cusco.

But Emperor Cápac also distributed part of the wealth

to the local population.

[Garrido] The Incas used metals

as political gifts.

It was very effective

for establishing alliances.

The generation of alliances made it possible to persuade

local populations to work for the empire.

[Narrator] This complex system of exchanging gifts and food

for work and wealth was the invisible glue

of the Inca Empire.

During its golden age,

Huayna Cápac ran a colossal and prosperous state,

where just a handful of Incas controlled a workforce

of 10 million from his palace.

The most rare and precious goods in South America

were amassed in Cusco,

including tons of fine gold and silver objects.

[Itier] Before the Inca Empire,

the best goldsmiths and metalworkers generally

inhabited the Pacific coast, particularly the north coast.

[Narrator] Despite popular belief,

these gold and silver crowns and ornaments

are not of Inca origin.

[Pachas] This object is characteristic

of the northern tradition of transforming the sacred bodies

of political and religious leaders

into ancestors.

[Narrator] The greatest artists of this period were the Chimús,

who came from Chan Chan and the north coast of Peru.

Before its conquest by the Incas in the late 15th century,

it was a flourishing city,

inhabited by several thousand craftspeople

living around huge palaces.

[Luján] This was a very busy area.

Craftspeople were constantly producing objects.

Here were workshops specializing in metalwork,

mainly silver and gold.

[Narrator] Under Inca occupation,

the Chimú craftspeople were forced to leave Chan Chan.

[Luján] When the Incas conquered the Chimú,

they discovered that the Chimú goldsmiths

were excellent artists, so they took these goldsmiths

and reproduced the same thing on the Inca sites.

[Itier] The capture of Chan Chan by the Incas

was a crucial moment in the development of their state.

They took all their goldsmiths to Cusco,

where they made the extraordinary Chimú

gold and silver jewelry

that became the basis of Inca goldsmithing.

[Narrator] Thanks to the talented artists of Chan Chan,

Cusco acquired the best metalworkers in the Andes.

Today, some rare treasures that escaped the greed

of the Spanish conquerors

are housed at the Larco Museum in Lima.

[Pachas] Many of the items were looted, melted down,

and transformed into metal

that was shipped out of ancient Peru after the conquest.

[Narrator] These metals, so precious to Europeans,

did not have the same value for the Andeans.

[Pachas] Metals were not used as a raw material

for exchange like money.

They were a sacred expression.

[Garrido] They weren't used

for commercial transactions.

They didn't have the same value

as in Europe or Asia.

[Narrator] The most precious and valuable commodity

in ancient Peru was textiles.

[Haydée Quiroz Malca, translated] Textiles were used

as objects of exchange,

like a means of payment, but an exchange of favors.

It was a form of currency that had a very, very high value.

[Narrator] Essential for protection

from the harsh sun and cool climate,

or to display social status, the fabrics were coveted gifts

for community leaders in order to forge alliances.

The finest weavings in South America

came from the Cajamarca region

in the north of the Inca Empire,

where several women's groups

still weave using ancient techniques.

[Malca] It's a long tradition that has been passed down

from generation to generation.

The craftswomen and artists of San Miguel are an example

of cultural resilience

as they keep their cultural heritage alive.

[Narrator] Under the Inca Empire,

textile production was so valuable

that the state controlled the entire industry.

The Incas supplied wool from its herds of llamas and alpacas

to communities who, in return, produced fabrics.

[Malca] People don't see it as exploitation,

but as an exchange.

So in exchange, you're going to give me a job,

and it will be a very fine one.

[Narrator] Textile production relied

on small community workshops,

as well as factories in the empire's major cities,

like Cusco and Pachacamac.

On the Pacific coast,

the 1,000-year-old site of Pachacamac

was transformed by the Inca occupation

into one of their main administrative centers.

They marked the landscape here with the Temple of the Sun

and a huge structure called an Acllahuasi.

[Rocio Villar Astigueta, translated] At Pachacamac,

the Temple of the Sun and the Acllahuasi

are political institutions that serve to control the area

and also to demonstrate the presence and power

that the Incas had on the central coast.

[Narrator] Acllahuasi means "house of chosen women"

in Quechua.

[Astigueta] There are open spaces in this building

where chroniclers tell us that women worked together

on various manufacturing jobs.

[Narrator] These women created the most important products

for the empire.

[Astigueta] The Acllahuasi functioned as a political system

that supported not only the governments of the empire

but also its economy.

[Narrator] In each district, the Incas organized

work, trade, and production

for the benefit of the elite and the royal family.

But Huayna Cápac was faced with a problem--

how to distribute the specialist workforce

across his territory.

♪ ♪

When the Incas arrived on the slopes of Machu Picchu,

thousands of workers colonized the region

to carry out the works.

Nearly 400 people lived there year-round,

some of the best experts in the empire.

Traces of various handicrafts were found where they worked.

♪ ♪

[Flórez] This is where they worked.

We've identified workshops for carving,

and we have a space further down

where we found evidence that they carried out metalworks.

[Narrator] In this area, the buildings are simple.

They are functional spaces.

[Flórez] All the people involved in farming

or maintaining the site,

they don't actually live inside the city.

They live on the outskirts.

[Narrator] In the tropical forest

surrounding Machu Picchu,

hundreds of burials have been found over the last 100 years.

[Elva Torres Pino, translated] These human remains come

from normal working-class people

who developed various economic skills

such as agriculture, stonecutting, and construction.

[Narrator] Remains are studied to find out more

about the individuals-- their age and sex,

as well as their occupation-- by looking for bodily traumas.

[Pino] The bones speak to us.

They tell us about their life.

We can see people who have worked with stone

have this type of muscular deformation

created from the force of striking.

[Narrator] To find out the origin of these craftspeople,

we need to look deeper.

The chemical composition of their teeth

can reveal their diets.

And studying genes can compare their DNA

with that of other pre-Hispanic remains

found throughout the Andes.

[Pino] In the DNA analysis, we found individuals

who had come here at a very young age

and had eaten food from other places.

[beeping]

[Narrator] Comparative biological analyses show

that many of the workers buried around Machu Picchu and Cusco

came from faraway regions in the Inca Empire.

[Pino] The results of these DNA samples show

that there has been a population movement

from the high plateau to the north

and from the coast to the south.

[Narrator] The majority of workers in the empire

were not Incas.

They came from conquered peoples

who were displaced according to the needs of the state.

[Pino] These are specialists who come on-site

where expertise is missing, where their work is needed.

So the Inca state circulates people

who can carry out work in different places.

[Itier] It's estimated that out of the Inca Empire's population

of 10 to 12 million,

between 3 and 4 million people were displaced.

[Narrator] These population movements enabled the Incas

to colonize remote valleys and make use

of the best craftspeople in the royal estates.

By integrating and developing ancestral techniques,

the Incas managed to tame a hostile natural environment

in order to feed their population.

And by employing 10 million people

to exploit the immense resources of his territory,

Huayna Cápac reached new heights of power and wealth.

But the splendor of the Inca Empire

was in a fragile state of balance.

Compulsory labor and forced displacement

was not accepted by all.

In the North, Huayna Cápac spent a large part of his reign

fighting off rebellions by the Chachapoyas,

Chimús, and Cañaris.

During one of these military

campaigns, around 1528,

the third Inca emperor

suffered from an unknown illness and died.

[Baca] When Huayna Cápac died,

the state was already in decline.

[Narrator] Only a century after its birth,

the Empire of the Sun entered its twilight years.

How did such a powerful empire collapse so suddenly?

At the peak of their glory,

the Sons of the Sun suffered a brutal downfall.

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