When researchers sifted through the ancient garbage of the Byzantine Empire's city of Elusa, they discovered clues of the city's destruction in the rubble.

The team's findings from the garbage told a different story from what historians used to believe about the collapse of the ancient city found in what is now the Negev desert in Israel.

According to National Geographic, it is widely believed that the Byzantine Empire in the Negev collapsed with the dawn of the Islamic period in the mid-seventh century. It has been said that key changes in trade and wine production greatly affected Elusa, ushering in their eventual decline. It turns out the real reason came a century before the Islamic period's arrival.

In a study published in the journal PNAS, scientists excavated urban garbage dumps in the perimeter of Elusa. With their findings, the team discovered that a quick and intense climate shift caused by volcanic eruptions brought about the demise of the Byzantine city.

Digging Through Mounds of Trash

Guy Bar-Oz, an archaeozoology professor at the University of Haifa, and the rest of his team trained their attention on Elusa's dumps. After all, they point out, the end of trash collection would likely coincide with the end of the city.

Through excavating and carbon dating the material found in the trash mounds, the researchers found that Elusa stopped collecting trash in 550. It is much earlier than they expected and predated the beginning of Islamic rule in the region.

During this period, the Roman Empire was thriving, according to Baz-Oz. Instead of showing signs of success, however, Elusa was already exhibiting signs of decline in the garbage.

"Instead, we are seeing a signal for what was really going on at that time and which has long been nearly invisible to most archaeologists — that the empire was being plagued by climatic disaster and disease," Bar-Oz told Live Science.

A Climate Shift That Triggered The End

The collapse of Elusa occurred during a time period of rapid climate change called the Late Antique Little Ice Age, which was revealed in a study published in Nature Geoscience in 2016.

This ice age, which lasted from 536 to 660, was the result of a series of volcanic eruptions in 536, 540, and 547. The eruptions blocked out the sun and triggered a chill to settle over the northern hemisphere for over a century.

Food shortages due to the extreme climate shift may have been a factor, but scientists told National Geographic that the cooler climate may have even been beneficial to the deserts of Negev.

It is possible that the economy of Elusa collapsed with less demand for their wine and other commodities outside the city.