PHONSAVAN, Laos — Archaeologist Eiji Nitta dug and scraped. The answer to the puzzle of the giant stone vessels scattered throughout the Plain of Jars in northern Laos lay, he believed, not in their material or their contents, but in what lay under them.

Within two weeks, the Kagoshima University professor had uncovered enough evidence to formulate probably the most significant theory yet to explain and date one of Asia’s great enigmas.

“For over 60 years, Western and Southeast Asian archaeologists have accepted the theory that the jars date back more than 2,000 years,” said Nitta, a professor at Kagoshima University’s Center for Comparative Archaeology and an expert in the prehistory of Southeast Asia. “Until now.”

For centuries, local villagers have passed down a legend that says the hundreds of stone jars scattered across the windswept plains of Xieng Khuang Province, located 300 km northeast of Vientiane, were the product of an elaborate drinking binge some 1,500 years ago.

According to the myth, during a battle on the Plain of Jars, an evil king was defeated by a valiant one, Khun Jeuam, who ordered the construction of the stone vessels to brew wine for a celebratory party. Some believe the warriors were somewhat larger than present-day Laotians and actually used the vessels as drinking goblets.

The legend has one slight flaw: The average weight of the urns is 700 kg, and the biggest, known as King Jeuam’s Cup, weighs between 10 and 15 tons.

The jars were first brought to the attention of Western archaeologists by Frenchman Henri Parmentier in the early 1920s and the geologist, paleobotanist and archaeologist Madelaine Colani a decade later. Both found evidence that the jars had contained cremated bones and a variety of other artifacts, suggesting they were more likely to have been sarcophagi.

Parmentier found beads, baubles, axes, stone ear rings and human bones in the jars, but by the time Colani conducted her excavations the sites had been heavily plundered by local villagers.

The Strasbourg-born Colani was known for her intrepidity: Together with her sister Eleonore, Colani carried out archaeological digs throughout Indochina from around the turn of the 20th century until her death in 1943. In the 1920s, she made significant discoveries of a hunting-foraging culture in Hoa Binh Province, Vietnam, which put the archaeological record in Indochina back over 18,000 years.

At the Plain of Jars’ Ban Ang site, also known as Site 1, Colani unearthed a large number of objects from around the jars, including bronze and iron tools that she believed had been used to carve the jars.

She also found bronze bells and bracelets, which she took to be burial offerings of the kind Parmentier had found. Another landmark discovery by Colani was the excavation of a cave near the site, whose blackened northeastern wall and natural chimney vents suggested that it had been used as a cremation chamber.

Colani’s findings and conclusions were documented in a 600-page monograph titled “The Megaliths of Upper Laos,” in which she claimed that the stone jars were funerary urns carved by Bronze Age people some 2,000 years ago.

This theory had gone largely unquestioned by archaeologists for over 60 years, until Nitta, along with members of the cultural artifacts section of Fukuoka City’s education board undertook a two-week excavation at the Ban Ang site in 1996, the first since Colani’s survey.

“Since (her) work in the 1930s, we have had very little information about the Plain of Jars,” Nitta said. While France’s presence in Indochina around Parmentier and Colani’s time (Laos was a French colony until 1953) had smoothed the way for their excavations, war and restrictions on visitors to the communist country had made it “very difficult for foreign archaeologists to visit Laos since,” he added.

“I was eager to get more archaeological information about Laos,” said Nitta, whose main area of specialization is neighboring Northeast Thailand and Vietnam.

During their two-week excavation, Nitta and his team dug four test trenches around one of the stone jars at Ban Ang and found seven flat stones, each covering a pit about 20 cm in diameter and 60 cm deep. In addition to uncovering some iron knives and clay ear rings, they found that six of the pits contained human bones while the seventh concealed a 60-cm-long burial jar containing small pieces of bone and teeth.

The pot intrigued Nitta, as it was coated in a kind of lacquer: “It was very recent in terms of prehistoric Southeast Asia,” he said. “It looked like the pottery work of the Khmer Dynasty, which would maybe date it to the ninth or 10th century.”

Nitta concluded that these pits were examples of “secondary burial,” a process whereby the bones of the deceased are dug up and ritually reburied in jars.

In Laos, Nitta explains in his “Comparative Study on the Jar Burial Traditions in Vietnam, Thailand and Laos,” there are two stages of jar burial: First the collection of small bones and teeth are placed in a jar and buried (secondary burial); the second is the digging up and cremation of those bones in separate jars — hence the jars that can be seen on the plains of Xieng Khuang today.

Since the lacquered jar he had unearthed could be dated to the ninth or 10th century A.D., Nitta concluded that the massive jars above must date to no earlier than this, and probably later.

Another significant discovery by Nitta was the carving of a human figure on the side of the jar he had dug around. The figure showed a human with hands held aloft and was the first anthropomorphic image recorded at Ban Ang site.

At a nearby market that he visited during his trip, Nitta bought a tool still used by local villagers to crush betel nut. “On it’s base was carved the same figure,” Nitta said. “It’s a traditional motif that still lives on in Xieng Khuang today.”

Yet Nitta could not explain why none of the other jars at Ban Ang feature such carvings or why there is such variation in their sizes. “I believe it may indicate status, a system of hierarchy,” he said.

Nitta also hypothesized that Xieng Khuang’s strategic position was one reason for the cemetery on the Plain of Jars.

The province, he pointed out, is a crossroads for east-west transportation between the coastal area of North Vietnam and the hill lands, and also between South China to the north and the rest of Southeast Asia to the south.

“So much information and so many commodities passed through Xieng Khuang,” Nitta said. “It was, and still is, one of the most important places in the history of Laos.”

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