Two summers ago, while snorkeling in the marshy streams of the Tollense River on Germany’s Baltic coast, a 51-year-old truck driver named Ronald Borgwardt made a startling discovery.

Poking around in the peat, he picked up a six-inch-tall bronze figurine with an egg-shaped head, looped arms, knobby breasts and a nose that would make an anteater envious.

The statuette, sporting a belt and a neck ring, was only the second of its kind unearthed in Germany, though the 13th found near the Baltic Sea. The first turned up around 1840. All are similar in shape and proportion.

“The most recent statuette poses an archaeological riddle,” said Thomas Terberger, an archaeologist and head of research at the Lower Saxony State Office for Cultural Heritage, in Germany. “What was it, how did it get there and what was it used for?”

Remarkably, 24 years earlier, while paddling through the same swamp, Mr. Borgwardt’s father had spied a bunch of bones jutting from a bank. He fetched his son and together they scavenged in the muck. Among their finds were a human arm bone pierced by a flint arrowhead, and a two-and-a-half-foot-long wooden club that resembled a Louisville Slugger.

More exploration of the area yielded the skeletons of a half-dozen horses, scores of military artifacts and the remains of more than 140 individuals, most of them men between the ages of 20 and 40 who showed signs of blunt trauma. Virtually all the relics have been traced to around 1,250 B.C., suggesting that they stemmed from a violent episode that may have played out over a single day.

A 2013 geomagnetic survey revealed that this narrow stretch of the Tollense Valley was once part of a trade route bisected by a 400-foot stone-and-wood causeway that had been used to transport amber to points on the Mediterranean and Adriatic Sea. The amber road predated the bloodshed by at least five centuries.

Today the area is considered Europe’s oldest battlefield site. “Although the region was sparsely populated 3,270 years ago, upward of 2,000 people were involved in the conflict,” said Dr. Terberger, who helped start a series of excavations based on the Borgwardts’ original discoveries.

In a paper published Feb. 12 in the archaeological journal Praehistorische Zeitschrift, Dr. Terberger and five colleagues propose that the statuette found by the younger Mr. Borgwardt dated to the seventh century B.C. and was either a balance weight, an object of worship or a combination of both.

“The unanswered question is why the figurine wound up in a river valley along a trade route hundreds of years after a large battle took place there,” Dr. Terberger said. “Did this happen by accident, or was the setting a place of commemoration for a 13th-century B.C. conflict still present in the oral history of the Late Bronze Age people? And if the statuette depicted a goddess, did she play a role in a primitive weight system?”

Eat your heart out

Lorenz Rahmstorf, a professor of Prehistoric Archaeology at the University of Göttingen and a co-author of the study, said weights and scales first came into use around 3,000 B.C. as trade developed in Egypt and Mesopotamia; the first weighing devices were a simple system to assess the value of goods, consisting of two plates attached to an overhead beam fixed on a central pole. Sumerian texts feature the earliest mentions of a weight unit, the mina, which tipped the scales at about 500 grams, or 18 ounces.

Balance scales spread to the Aegean in the west and to the Indus Valley culture of South Asia in the east. By the middle of the second millennium B.C., weight systems turned up in Italy, and, by 1,350 B.C., north of the Alps.

“Sets of small bronze weights and balance beams in bone were mixed together in bags, and placed next to the dead in a number of graves from Eastern France and Southern Germany,” Dr. Rahmstorf said. “We do not yet have clear evidence for when weighing equipment was introduced to North Germany and Scandinavia.”

No ancient civilization attached stronger symbolic and spiritual significance to scales than the Egyptians from the second millennium B.C. to the Roman Period. Their most solemn otherworldly moment was the Weighing of the Heart.

It was the Egyptian belief that after a person died, Anubis, the jackal-headed god of embalming, led the deceased to the judgment hall of Osiris, where the dead heart was weighed against a feather of Maat, the personification of truth, justice and the cosmic order.

If a heart was pure, it would be as light as the feather, and the deceased was deemed worthy to enter the afterlife. Thoth, master of knowledge and patron of scribes, stood by to record the final verdict, and under the balance, Ammut the devourer — head of a crocodile, forepart of a lion, hindquarters of a hippopotamus — sat ready to consume the damned.

“Balance had to be reached so that your heart didn’t get eaten by dear Ammut,” said Kara Cooney, a professor of Egyptian art and architecture at the University of California, Los Angeles.

The first definitive weights are pebbles from the Second Dynasty of ancient Egypt, which lasted from 2,890 B.C. to 2,686 B.C. “Some of the stones were engraved with parallel incisions, some with hieroglyphic inscriptions,” Dr. Rahmstorf said. “Metal weights became common only in the following millennium.”

A wealth of goddesses

A majority of the 13 bronze figurines were recovered in or around rivers near the Baltic coast — six turned up on the Öresund, a strait that separates the Danish island of Zealand from the Swedish province of Scania. The statuette found in the Tollense by Mr. Borgwardt is the largest and, at 155 grams, or about 5.5 ounces, the heaviest.

It was long believed that the economy of northern Europe during the Bronze Age had been based on gift exchange rather than trade. The idea that the bronze figurines represented measurements of an early Scandinavian weight system was advanced in 1992 by the Swedish archaeologist Mats Malmer.

After figuring in erosion and weight loss, Dr. Malmer analyzed the 12 existing “Goddesses of Wealth” for weight consistency and proportionality. His calculations indicated that the weight of the statuettes could be expressed in grams as multiples of a common denominator, 26.

On a recent afternoon in his office at the University of Göttingen, Dr. Terberger reeled off the weights of some of the figurines: 55 grams, 85 grams, 102 grams, 103 grams, 103 grams, 104 grams, 106 grams, 110 grams, 132 grams, 133 grams. From across the room, his departmental colleague Dr. Rahmstorf said, “Not every figurine fit the scheme perfectly, but most were quite close.”

Although the units of weight seem to have been standardized, Dr. Rahmstorf doubts that the statuettes were used as weights. “It is possible that they were weight-regulated,” he said. “By which I mean the amount of metal used may have been weighed out.”

Still, the sample of figurines is small. And so far, unambiguous weights and scales from Northern Germany and Southern Scandinavia are missing. But some objects from the Late Bronze Age in these regions are possible candidates for weights: stone discs with a horizontal groove.

Dr. Rahmstorf’s initial analyses with his colleague Nicola Ialongo are promising, but he cautioned, “these would be heavy weights of over 100 to several thousand grams.” Because there are no texts and inscriptions from that era of northern Europe, “currently, the existence of weights and scales in that area is likely but still only hypothetical.”

Weight watchers

Back when Dr. Malmer came out with his theory, the statuettes were widely dismissed as artistically inferior to other figurines from the Late Bronze Age. “The hypothesis has been put forward that these statuettes are cheap mass products, owned by poor people as household gods,” he wrote in the journal Antiquity.

Dr. Terberger demurs. “All in all, 13 figures of this type do not support the idea that the statuettes were cheap household gods,” he said. “In the past they were interpreted as goddesses, but they don’t match any deities widely worshiped at that time.”

On the other hand, Flemming Kaul, a senior researcher at the National Museum of Denmark, is not persuaded that the statuettes were weight-regulated. “For me, the gram numbers seem much too random, and the ‘statistical material’ too low to draw any such conclusion,” he said.

Dr. Kaul speculated that the statuettes were divinities, although not necessarily part of a defined pantheon. “These figurines may have possessed magical powers tied to the ability to produce offspring,” he said. “They could very well be seen as charms or votive pieces related to childbirth — the most dangerous time in a woman’s life.”

How might the Borgwardt figurine have ended up at the bottom of the river? “On the Tollense trade route, with Nordic amber, a traveler offered up her amulet to the local water nymphs for further good luck on the voyage,” Dr. Kaul said. “Perhaps she parted with the talisman as a token of friendship or perhaps to promote life, fertility and cosmological order in the — for us — mysterious world of Bronze Age religion.”

For now, the riddle remains unsolved.