New findings reveal that two skeletons discovered decades ago beneath the floor of a historic Byzantine church in Greece belong to local inhabitants of the 13th century, ruling out long-standing rumors that they were associated with famous early Christian martyrs or high-ranking medieval Italian nobility. The research, published in the Journal of Medieval History, combines skeletal biology, genetic sequencing, and historical archives to reconstruct the identities of these anonymous individuals.
The Basilica of Saint Isidore sits in the capital of Chios, an island in the eastern Aegean Sea. The site represents the oldest Paleo-Christian monument in the area, featuring a complex architectural history of rebuilds, ornate mosaic floors, and earthquake repairs. The church was originally constructed to honor Saint Isidore, a Roman soldier executed in the year 250 for his Christian faith, and Saint Merope, another early martyr associated with his burial. As empires rose and fell, the site endured pirate invasions, the Crusades, and shifts in regional control among Byzantine, Latin, and Genovese powers.
During rescue excavations in the 1980s, archaeologists found an anomaly beneath a fifth-century mosaic panel near the church nave. A solitary grave had been cut through the floor, holding the remains of two individuals. The specific placement of this tomb, devoid of identifiable grave goods or artifacts, posed a significant challenge for dating the burials. Local tradition and historical speculation offered several possibilities for who might warrant such a prominent resting place. Some thought the remains might belong to the historic martyrs themselves, or perhaps to a Genovese noble, such as Benedetto Zaccaria, who governed the island in the early 1300s. Resolving this question required extracting physical, chemical, and genetic clues locked inside the bones.
An interdisciplinary research team led by physical anthropologist Anagnostis P. Agelarakis, alongside archaeologists, historians, and geneticists including Iosif Lazaridis of the David Reich Laboratory at Harvard Medical School, revisited the artifacts and skeletal material. The initial archaeological digs were overseen by Charalampos I. Pennas. Because one of the skeletons was severely fragmented and degraded by soil conditions and past human disruption, traditional physical examinations of the bones yielded an incomplete picture.
To build a clearer profile, the researchers took small bone and dental samples from both individuals to extract ancient DNA and perform radiocarbon dating. Radiocarbon dating estimates the age of organic material by measuring the steady decay of carbon-14 isotopes absorbed during an organism’s life. This technique narrows down the historical window in which a person lived. Meanwhile, genetic sequencing allowed the team to determine biological sex, measure familial relatedness, and map the individuals’ ancestral origins. By comparing the ancient DNA to genetic databases of both modern populations and past groups from the Mediterranean, the team could trace the geographic lineage of the two islanders.
The laboratory testing provided a precise profile of the two individuals. The genetic data confirmed that the primary burial belonged to a male, while the secondary, more fragmented skeleton belonged to a female. Analyzing chemical signatures in their teeth indicated that the male lived on a diet rich in carbohydrates and experienced severe dental issues, including an abscess that would have caused significant infection during his life.
The radiocarbon dates placed both lives squarely in the late 13th century. The female likely died between 1257 and 1300, while the male died between 1274 and 1303. This timeline completely eliminates the possibility that they were early Christian martyrs from the third century. It also rules out Benedetto Zaccaria, who died slightly later in 1307. Based on the calculated age differences at their respective times of death, they were not spouses. The DNA analysis also showed complete absence of familial relatedness, meaning they were neither mother and son nor siblings.
Their genetic ancestry points to deep local roots. The DNA profiles lack any markers tying them to Italian or Genovese populations. Their genomes align closely with modern Greek people from the Aegean islands and with Roman-Byzantine populations from neighboring Anatolia. This evidence suggests they were native islanders who lived through a highly turbulent era marked by shifting imperial borders, pirate raids, and local wars. The male even carried an ancient lineage marker on his Y-chromosome often associated with populations further east, hinting that his distant paternal ancestors might have migrated through the Hellenistic empires of antiquity before settling in the Greek islands.
The physical arrangement of their grave shows the female was buried first. A decade or so later, the grave was reopened to inter the male as the primary burial, with the female’s remains respectfully shifted aside. Placing a grave beneath the mosaic floor of a major basilica implies a certain level of honor or community importance. The chronological data corresponds with a time when the broader church structure was largely in ruins, yet the congregation still utilized the site as a sacred space for a handful of burials.
Determining the exact identities of these people remains elusive. The advanced deterioration of the female’s skeleton severely restricted the amount of physical data scientists could gather regarding her height, physical health, or exact age at death, making the shift to molecular analysis essential. The absence of inscribed grave markers, jewelry, or historical records explicitly naming the deceased limits the story to biological and chronological outlines.
Open questions remain regarding why these two unrelated individuals shared a grave in such a high-status location. They might have been wealthy benefactors, respected clerics, or prominent community members afforded an honor modeled after the saints. While modern laboratory tools can pinpoint when and where they lived, their exact roles within the medieval society of Chios still await further archaeological context.
The paper, “Sacred Space and Identity: Insights from Archaeoanthropology, Historiography, and Archaeogenetics at the St. Isidore Cathedral of Chios Island, Greece,” was authored by Anagnostis P. Agelarakis, Charalampos I. Pennas, Iosif Lazaridis, Edward A. Reno III, and Argiro Agelarakis.