Moche warrior pot (made between 100 and 700 AD), from Peru

So far this week, we've been in Damascus handling the first Islamic coinage, and in Suffolk with the great Anglo-Saxon burial ship at Sutton Hoo. The famous helmet found there leaves no doubt that it was the grave of a warrior chief. If pursuing this week's themes of war, empires and faith, we spin the globe of the world around 650 AD on its axis, and if we keep moving west to what is now Peru, we're going to find there another warrior commemorated.

Here in Peru, a forgotten people have left to history not just a face, but an entire three-dimensional portrait of their fallen warrior. And from this small sculpture - from the clothes and the weapons it shows, from the way it was made and buried - we can begin to unravel the mystery of a lost civilisation. It couldn't possibly have had any contact with the societies then flourishing in Europe and Asia but, astonishingly, it shows a great number of similarities with them. What does that say about what it means to be human?

"I suppose you could sort of compare them in our culture to Toby jugs, because you sort of imagine people sort of sitting round getting smashed really, and each having their own characteristic drinking vessel." (Grayson Perry)

"We had indeed a smoking gun, and also a plethora of sacrificial acts on the human remains themselves, on the bones." (Professor Steve Bourget)

History has been kind to only some American cultures. The Aztecs and the Incas have an unshakable place in our collective imagination, but if I were to ask you where the Moche called home, you might be a little more hesitant. Experts in early American history are slowly coming to terms with civilisations that ran in parallel with, and were every bit as sophisticated as, their most advanced European counterparts, and the Moche are at the centre of that rethinking of the American past.

Around two thousand years ago, the Moche people built a society that was probably the first real state structure in the whole of South America. It developed in the narrow strip of almost desert land between the Pacific Ocean and the Andes Mountains. It was a civilisation that lasted over eight hundred years - from the rise of the Roman Empire around 200 BC to the Islamic expansions around 650 AD, and it's a history accessible to us now only through archaeology, as the Moche have left no writing. But what we do have from them is pots.

I'm in the Enlightenment Gallery at the British Museum, where we have an array of these South American pots on show. They're over 1,300 years old, and they're an extraordinary sight to look at, ranged on the shelves: a series of small sculptures about 9 inches (25cm) high, made out of clay, brown with cream painting on it, and they conjure up a whole world. There's a pair of owls, there's a bat, there's a sea-lion eating a fish, there are priests and warriors, and all of them sit like small sculptures, but with a looped handle and a spout because, as well as being statues, they're jugs. What we have here in fact is a pottery representation of the Moche universe, and I want to choose one of these pots to take us further into that world of Peru 1,300 years ago.

He's a kneeling figure of a young Moche warrior. In his right hand he holds something that actually looks quite like a microphone but is actually a mace, it's a head-cracker, and on his left forearm he carries a small circular shield. His skin is a deep copper colour, and his eyes are staring white - a very, very arresting gaze.

Before we try to squeeze evidence from them about the society they represent, I want to take a moment to admire these pots simply as great works of art. The Moche were master-potters, and so their creations can best be judged by another master-potter - the prize-winning Grayson Perry:

"Well, he's a dumpy little fellow, and they're beautifully modelled - they almost look like they've been burnished. If I was to get this effect, I'd probably use the back of a spoon, but they've probably used some sort of bone implement or something. But they were experts in mould technology, and they used a lot of moulds to replicate these things a number of times - something I always call a sort of relaxed fluency, in that you imagine the person who's made it has made hundreds of these things, and they're kind of riffing on it, and so they're incredibly confident when they're making it. And I suppose there's something for me about this figurine, and Moche pottery in general, that feels kind of familiar to me as an Englishman. It feels like a culture that has a very strong community bond, with lots of joking and human sacrifice!"

Well, maybe he's right! Grayson Perry naturally warms to the accomplished confidence of these potters, but I'm not quite so certain as he is about the jokey side of Moche pottery. These pots seem to have been made entirely for burials and sacrifice - and to be about life and death at its most solemn.

Excavations of Moche burials often uncover large numbers of these decorated pots, sometimes many dozens of them, all carefully ordered and organised around repeated themes and subjects. The sheer quantity of pots that survive tell us that Moche society must have operated on a considerable scale. Pots like this must have been an industry, with elaborate structures of training, mass-production and distribution.

Moche territory stretched for around 350 miles (560 km) along the Pacific coast, and theirs was, literally, a narrow existence - bounded by the ocean on one side and the mountains on the other, usually with just desert in between. But their largest settlement, at Moche itself, was the first real city in South America, with streets, canals, plazas and industrial areas that any contemporary Roman town would have been proud of. The remains of the canal network that they used to channel the rivers flowing from the mountains are still visible today. They also exploited the extremely rich waters of the Pacific for fish, shellfish, seals, whales and birds. There's one pot for example, in the British Museum, that shows a Moche fisherman in a large boat catching tuna. Carefully managing and irrigating their environment, the Moche grew maize and beans, farmed llamas, ducks and guinea-pigs, and as a result, were able to sustain a population three times as large as the area does today.

And yet, as is usually the case in human history, it is not the great acts of water engineering or agriculture that a society honours in its works of art. It's war.

The celebration of war and warriors is a central aspect of Moche art, and this certainly reflects the importance of the warrior to their society - just as to the Romans or the Anglo-Saxons in Europe. For the Moche, though, war and religion were joined together in a way that would perhaps be less familiar to Europeans. Fighting, for the Moche, held a very strong ritual aspect to it. For protection the warrior carries a small round shield, not much bigger than a dinner plate, and a heavy wooden club that could crack a skull with ease. His decorated clothes suggest he is a young man of high status, but he is clearly a foot soldier. There were no horses at this time in South America - that came later with the Europeans - and llamas, as you'll imagine, don't make great cavalry. So even the elite among the Moche travelled and fought on foot.

Other pots show scenes of warriors fighting each other in single combat, armed, like this figure, with clubs and small shields. These may well be scenes of real fighting, but they also appear to be part of a common Moche myth that we can piece together from groups of pots. Taken as a whole, they tell a gruesome story. To lose a contest like this meant much more than just losing face. The defeated warrior would be sacrificed, decapitated by an animal-headed figure and his blood then drunk by others. This bloody narrative, told by the Moche pots, is by no means just an artistic invention. As Steven Bourget, a leading archaeologist, has found at his archaeological excavations, it happened:

"We excavated this sacrificial site, which included about 75 male warriors sacrificed during various rituals, and we also found the tombs of two sacrificers. And in one of the tombs was also included a wooden club, covered with human blood - so we had indeed the 'smoking gun' - and also the victims themselves, side by side within the temple.

"We found that these were male warriors. Robust, strong, males aged between 18 to more or less 39 years of age. They had a lot of ancient injuries consistent with battles, but also had a lot of fresh injuries, a lot of cut marks on the throats, on the arms, on the faces, indicating that most of them have had their throat cut. And a few of them had the skin of their face removed, arms separated from their bodies, some of them were de-fleshed completely and transformed into skeletons - even in one case two human heads transformed into some kind of container."

It's grim and gripping stuff. And there's a lot of mystery still to unravel. The Moche stopped making these horror-movie pots, and indeed pretty much everything else, in the seventh century - roughly about the same time as the Sutton Hoo ship burial. Why? There are no written records of course, we've got to guess, and the best bet at the moment seems to be climate change. It appears there were several decades of intense rain, followed by a drought that upset the delicate ecology of their agriculture, and wrecked much of the infrastructure and farmlands of the Moche state. If that's what did happen, there would clearly be neither the time nor the resources to make pots. People did not entirely abandon the area, but their skills seem to have been used above all for the building of fortresses, which suggests a world splintering in a desperate competition for diminishing natural resources. Whatever the cause, in the decades around 600 AD, the Moche state and civilisation collapsed.

To most of us in Europe today, the Moche and other South American cultures are unfamiliar and unnerving. In part, that's because they belong to a cultural tradition that followed a very different pattern from Africa, Asia and Europe. For thousands of years, the Americas have a separate parallel history of their own. But as excavation unearths more of their story, we can see that they are caught in exactly the same predicaments as everybody else - harnessing nature and resources, avoiding famine, placating the gods, waging war. And as everywhere else, they addressed these problems by trying to construct coherent and enduring states. In the Americas, as all over the world, these ignored histories are now being recovered to shape modern identities. Here's Steven Bourget again:

"I think one of the fascinating things that I am looking at when I look at Peru today, is that they are in fact in the process of doing what also happens in Mexico, perhaps in Egypt, and eventually I would believe China . . . where these countries who have a great ancient past build their identity through this past, and it becomes part of their present. So the past of Peru will be its future. And eventually the Moche will, I think, become a household name, just as much as the Maya or the Inca or the Aztec for that matter. Eventually it will become part of the world legacy."

The more we look at these American civilisations, the more we can see that their story is part of a coherent and strikingly similar worldwide pattern. A story that seems destined to acquire an ever greater modern political significance. And in the next programme, we're going to see what events of 1,300 years ago mean in contemporary Korea.