'As soon as you see the elephant tusks, you know that you are onto something," Ran Honglin, director of the Sanxingdui Archaeological Research Institute, told the camera at one point during an excavation carried out at the site in Guanghan city, Southwest China's Sichuan province, in 2020.

The previous November, six pits were discovered 33 years after the uncovering in 1986 of two pits that had disgorged a large amount of bronze and jade artifacts, among other things.

And anyone who had been part of the recent effort, the fruit of which now fills three galleries at the Shanghai Museum East, will tell you that the discovery of elephant tusks had invariably led to the discovery of bronzes and jades. In fact, most of the time, those who did the digging would be staring directly through the tightly packed tusks at those findings, still half-buried in earth.

"It was only during the more recent excavation that archaeologists started to get a deeper understanding of the formation, as well as the nature of those pits and their contents," says Hu Jialin, curator of the Shanghai exhibition, which is focused on the Bronze Age civilization of Sanxingdui.

Sitting in close proximity to one another, the pits — there are at this moment eight in total — are located within what seems to be a designated area within the archaeological ruins of Sanxingdui's walled city.

"Judging by what we have found so far, the city was zoned based on function. There was the palatial district, the residential district, the handicraft district and then the sacrificial district, where all the pits are," Hu says.

According to the curator, the immediate thought among archaeologists upon the discovery of the two pits in 1986 was that they were sacrificial pits where offerings or sacrifices were placed as part of religious or ceremonial rituals. This theory, however, was later called into question with the discovery of the archaeological site of Jinsha, 40 kilometers south of Sanxingdui.

"It is widely held that between 1100 BC and 600 BC, Jinsha was the seat of power for the ancient kingdom of Shu, which relocated to the site from Sanxingdui, after having built a splendid civilization there between 1600 BC and 1100 BC," Hu says.

A new theory came along: The pits were where the Shu people buried their much-treasured ceremonial and sacrificial wares, right before they were forced to flee to Jinsha, where the fortune of the kingdom continued to wane. The proposition remained popular for a long time, until it, too, was cast into doubt with the discovery of the six additional pits in November 2019.

"For one thing, the eight pits were arranged in an orderly fashion in relation to one another, something that would be unlikely to happen if they had been dug out in great haste," Hu says.

The 2020-2022 excavation, carried out with the full assistance of modern technology, revealed a highly stratified burial pattern, which in turn offers a tantalizing glimpse into what actually took place more than 3 millennia ago, around the 11th century BC.

"Take Pit No 4 for example. The initial 1.4 meters were all dirt. Beyond that it was a 15-centimeter-thick layer of ash, which led to another layer of dirt sprinkled with bits and pieces of bronze, bone and gold artifacts," says Ran, the archaeologist. "'This is about all of it?' We thought to ourselves at the time. And that's when the elephant tusks revealed themselves, through which we got a peek of the bronze and jade items lying underneath."

Months of hard work ensued, during which archaeologists carefully lifted every single artifact out of the ground, before arriving at the bottom of the pit. "By that point, we were finally able to reconstruct the whole burial process, step by step," Ran says.

"First, land was leveled and big holes measuring no more than 2 meters deep were dug. Artifacts were placed inside: pottery first, followed by jade and gold objects, and then by bronzes. On top of these objects, a batch of ivory — around 50 pieces in the case of Pit No 4 — was laid before ash was poured in. When all this was done, the pits were again filled with soil, soil that had previously been removed during the digging of the holes," he says.

"As well as Pit No 4, we have seen the same pattern in other pits, most notably Pit No 3, where nearly 300 bronzes and 50 pieces of jade were found under the weight of more than 120 elephant tusks."

One thing is worth noting: The bronzes and jades, which were undoubtedly ritual wares, had been smashed and burned before they were buried. Red-hot ash resulting from the burning was poured onto the elephant tusks, causing the tusks themselves to be severely burned.

"However, as the clear layering indicates, the burning had been carried out not within the pits, but somewhere else, which supposedly wasn't very far away. The pits were only for burial after the completion of the burning," Ran says. "And the pits were very unlikely to have been created and filled at the same time: On several occasions, a bronze piece unearthed from one pit, a tree branch for example, has been found to be the matching part belonging to another piece uncovered in another pit."

Keeping in mind that the eight pits had collectively covered a land area of about 90 square meters, and held thousands of pieces of exquisitely crafted artifacts, the sacrificial ritual, if it indeed was such, must have been phenomenal.

"Break, burn and bury — if that's the typical ritual observance of Sanxingdui, then it was certainly not the only culture that had developed the practice," Hu says. "In fact, the burning and burying of ritual jades was routinely carried out during the Shang Dynasty (c. 16th century-11th century BC)," Hu says.

But there's one problem. Certain items excavated from the Sanxingdui pits, a grand bronze mask measuring at 135 cm in width for example, are viewed by most researchers as representing spirits or ancestors — objects to be venerated instead of offered.

In 2021, archaeologists discovered, in Pit No 8 — the largest of the eight pits — burned clay blocks, which they consider to be architectural remains.

"Given their coexistence with the ritual objects, these remains were likely to have come from temples of worship. But what kind of rites would involve the destroying of not only the offerings, but also the sacred objects and the temple of worship itself?" Hu asks.

"I am tempted to believe that the pits were formed as a direct result of the demolition of Sanxingdui's temple of worship and everything inside, a seemingly crazy act propelled by the abandonment of the original belief to which the temple had been dedicated."

In searching for clues for this religious and cultural turnaround, Hu looked at the 4th-century book The Chronicles of Huayang, which gave a fleeting mention of a certain ruler of the ancient kingdom of Shu "starting to build ancestral halls". (Huayang was an ancient name for the land of Shu.)

"Judging by all evidence, including the many bronze altars unearthed from the Sanxingdui site, the ancient kingdom, located within the upper reaches of the Yangtze River, was a theocracy with a belief system closely linked to the ones adopted by prehistoric cultures along the middle and lower reaches of the river," Hu says.

"What they had in common was the embrace of shamanism, in which shaman (wu in Chinese), believed to have the ability to communicate with spirits, played significant roles in society as intermediaries between the human world and spiritual realm."

Many bronze figures from Sanxingdui, some holding ritual items originating from the lower Yangtze River Delta region, are believed to be portrayals of shamans.

"In a sense, this had set Sanxingdui apart from the dominant culture existing in the Chinese heartland along the middle and lower reaches of the Yellow River, whose belief system was formed around ancestral worship," Hu says.

Although the two coexisted, and even overlapped for a long time, the latter was on a consistent rise, the influence of which spread southward from the Yellow River basin.

"In my view, the Sanxingdui culture must have eventually succumbed to those influences. And the construction of ancestral halls as mentioned in that 4th-century book signaled a religious reform, a radical departure that demanded the destruction of everything we are finding now," says Hu, pointing out that the pits and their contents were dated to the late Shang Dynasty.

That was when the people, who were to found the Zhou Dynasty (c. 11th century-256 BC), rose up against the tyrannical rule of the last Shang king. In doing so, they had enlisted the help of many political forces including the kingdom of Shu, according to The Chronicles of Huayang.

For material proof, some bronzes unearthed from Sanxingdui are believed to be war trophies from the fallen of the Shang Dynasty, which was known for its magnificent bronzes.

"Like their Shang predecessors, the rulers of the Zhou Dynasty conducted ancestral worship. For the kingdom of Shu to be taken into the fold, it probably had undergone some fundamental change that allowed it to align with this rising power, not just militarily, but also culturally and spiritually," Hu says.

"But of course, other incidents — natural disasters for example — may have occurred that resulted in a serious loss of faith among the Shu people in their original beliefs."

With that being said, the relationship between Shu and Zhou had proved to be one of love-hate. Oracle bones dated to the Zhou Dynasty have been found that referred to "military campaigns against Shu".

What happened in reality was extremely complicated, but one thing is for sure: By the end of the Sanxingdui culture in the 11th century BC, the influence of the Zhou Dynasty was already felt on the Chengdu Plain. At the Jinsha site, archaeological remains of wheat, grown by the people of Zhou in northern China, have been found.

After Jinsha, which lasted between 1100 BC and 600 BC, the ancient kingdom of Shu largely ceased to exist as one single political entity, according to Hu. It was ruled instead by a number of competing forces, a situation mirrored by what was happening in the realm of Zhou, where various vassal states fought with one another for military supremacy and territorial expansion.

One of them was the state of Qin, which in 316 BC conquered Shu, 95 years before it united China for the first time in history, in 221 BC.

Then what about the elephant tusks?

"Back then, elephants were probably native to the land of Sanxingdui. And elephant tusks, not unlike gold, were much-treasured resources that had not only embellished the life of locals, but also occupied a place of prominence in their culture and spirituality. They might have also been traded between Sanxingdui and other cultures," says Cao Dazhi, associate professor from Peking University's School of Archaeology and Museology.

Hu has his own theory. "In a form of sorcery popular in ancient China, a thing believed to have dominant strength was placed right on the top of something else representing a force one intended to subdue. In my opinion, that's what the tusks were there for: to prevail against whatever power and spirit embodied by the ritual bronzes and jades, and to make sure that they lay there underground without stirring," he says. "Or, perhaps, until the world was ready to hear their stories."