Chang and Eng Bunker were conjoined twins born in 1811 in the Kingdom of Siam, now Thailand, who became the most famous conjoined siblings in history and the reason the English language uses the phrase “Siamese twins.” Connected at the chest by a narrow band of cartilage and flesh, they lived 62 years without ever being separated, fathered 21 children between them, and ran a prosperous farm in rural North Carolina. Their story is stranger, more layered, and more revealing of the society they moved through than most people realize.
From a Fishing Village to the World Stage
Chang and Eng were born on May 11, 1811, in a small village along the Mekong River in what was then Siam. Their mother was Chinese-Thai, and the family made its living from fishing and duck farming. Though local accounts suggest the twins attracted curiosity in their community, they were not outcasts. They swam, worked, and moved through daily life with a degree of coordination that impressed everyone who saw them.
Their lives changed in 1829, when a British merchant named Robert Hunter and an American sea captain named Abel Coffin arranged to bring the teenagers to the West. The twins arrived first in Boston, where they were examined by physicians and exhibited to the general public.1PubMed. Exhibiting monstrosity: Chang and Eng, the ‘original’ Siamese twins From there, they toured the United States and Europe for years, appearing before packed audiences and submitting to medical inspections at hospitals and learned societies. They were billed as the “Siamese Twins,” and the label stuck so thoroughly that it became the generic English term for all conjoined twins for the next two centuries.
The exhibition years were profitable but exploitative. Hunter and Coffin controlled the twins’ earnings and schedule for the first several years, and the relationship soured. By the time Chang and Eng reached their early twenties, they had grown fluent in English, understood the business, and severed ties with their managers. They began touring and exhibiting themselves on their own terms, keeping their income and making their own decisions about when to appear and when to refuse. That pivot from managed curiosity to self-directed career is one of the more overlooked parts of their story.
The Band That Bound Them
Chang and Eng were connected at the lower chest by a flexible band of tissue roughly five inches long and about eight inches in circumference. The medical term for this type of connection is xiphopagus, meaning the junction occurs at or near the xiphoid process, the small piece of cartilage at the bottom of the sternum. Xiphopagus twins are among the rarer configurations of conjoined twinning, and a large review of 36 reported cases spanning 300 years found that the extent of fusion varies considerably from one pair to another.2American Journal of Obstetrics and Gynecology. Xiphopagus conjoined twins: A 300-year review of the obstetric, morphopathologic, neonatal, and surgical parameters
In Chang and Eng’s case, the connecting band contained a thin bridge of liver tissue, blood vessels, and cartilage. During their lifetime, multiple physicians debated whether separation surgery was possible. Some believed the shared blood vessels made it too risky; others thought the procedure was feasible with careful ligation. The twins themselves declined surgery. Over the years the band stretched somewhat, going from a tight connection that forced them to stand nearly face-to-face in childhood to a more flexible ligament in adulthood that allowed them to stand side by side. This gradual stretching gave them greater freedom of movement as they aged, and by their adult years they could walk, ride horseback, and do farm labor without extraordinary difficulty.
That same 300-year review of xiphopagus cases found a high rate of additional congenital abnormalities in this type of twinning, with cardiac defects appearing in roughly a quarter of cases and gastrointestinal abnormalities in about a third.3American Journal of Obstetrics and Gynecology. Xiphopagus conjoined twins: A 300-year review of the obstetric, morphopathologic, neonatal, and surgical parameters Chang and Eng were fortunate in that neither twin had major organ defects beyond their shared hepatic bridge. Their individual organ systems were largely complete and functional, which is a significant part of why they lived as long as they did. Many conjoined twins throughout history have not been so lucky.
Settling in North Carolina
After years of touring, Chang and Eng retired from public life in the mid-1830s and settled in Wilkes County, North Carolina. They became naturalized United States citizens, adopted the surname Bunker, bought land, and began farming. The choice of rural Appalachia was deliberate. They wanted stability, privacy, and a livelihood that did not depend on people staring at them.
In 1843, the twins married sisters Adelaide and Sarah Anne Yates, the daughters of a local landowner. The marriages raised eyebrows, and critics questioned the moral and legal dimensions of two conjoined men marrying two separate women. North Carolina law had no precedent for it, but neither did it explicitly prohibit the arrangement, and the marriages proceeded. Chang and Adelaide eventually had ten children; Eng and Sarah had eleven. Twenty-one children from two men who were never apart is a fact that tends to stop people in their tracks, and it prompted no end of speculation and crude humor during the twins’ lifetime and after.
The domestic logistics were handled with a system that the twins reportedly devised early in their marriages. They alternated between two separate households, spending three days at Chang’s home with Adelaide and then three days at Eng’s home with Sarah. The non-resident twin was expected to defer to the wishes of the twin whose house they were in. By all accounts this arrangement functioned for decades, though it introduced obvious tensions. Each twin had to be a permanent guest in his brother’s home half the time, and the wives had to accept the perpetual presence of their brother-in-law. The marriages survived, but they were not without friction, especially in later years when Chang’s health and temperament deteriorated.
The Bunker families were prosperous enough to own a considerable amount of farmland. They grew tobacco and other crops. They were accepted as members of their community, served as local taxpayers, and participated in the social life of rural western North Carolina. The twins joined the Baptist church and were involved in civic affairs. They were, in most observable ways, farmers and family men who happened to be physically inseparable.
Slavery and the Bunker Household
One aspect of the Bunkers’ life in North Carolina that modern readers find jarring is that they were slaveholders. They purchased enslaved people to work their farms, a practice consistent with the planter class they aspired to join in the antebellum South. Census records from the 1850s and 1860s list enslaved individuals as part of their household property. The twins, who had themselves been exhibited and in some respects commodified, became participants in the institution of chattel slavery. This uncomfortable fact complicates any simple narrative of Chang and Eng as sympathetic underdogs. They occupied a peculiar position in the racial hierarchy of the pre-Civil War South: immigrants from Asia who were accepted as white enough to own land, marry white women, hold enslaved people, and become citizens, even as they were simultaneously regarded as exotic curiosities.
The Civil War devastated their finances. The end of slavery eliminated a labor force they had depended on, and the broader economic collapse of the postwar South hit them hard. To recover some income, the aging twins returned to exhibition in the late 1860s, traveling with P.T. Barnum and touring Europe once more. The comeback tours were less successful than their earlier appearances, and the physical toll of travel weighed on them, particularly on Chang.
Declining Health and Death
Chang was the more volatile of the two and also the heavier drinker. By the late 1860s, he had suffered a stroke that left him partially paralyzed on one side. Eng remained healthier but was forced to accommodate his brother’s reduced mobility, essentially supporting Chang’s weakened body during every movement. The imbalance strained their relationship and made travel exhausting.
On the night of January 17, 1874, Chang died in his sleep. Eng awoke to find his brother dead and reportedly said, “Then I am going.” He died roughly three hours later. Whether Eng’s death was caused by shock, by blood loss through their shared circulatory connection, or by some other mechanism has been debated. The most widely accepted explanation is that Eng died of fright or cardiovascular shock upon realizing his twin was dead and that he was physically attached to a corpse with no possibility of separation in time. Their family had long feared this exact scenario and had arranged for a surgeon to attempt emergency separation if one twin died, but the surgeon did not arrive before Eng passed.
An autopsy was performed at the College of Physicians of Philadelphia. It revealed that the connecting band contained a bridge of hepatic tissue linking the twins’ livers and that the peritoneal cavities communicated through the band. There were shared blood vessels, confirming that surgical separation during their lifetime, while not impossible, would have been genuinely risky with the tools and techniques available in the nineteenth century. The autopsy cast of their connected torsos remained on display in Philadelphia for many years and became an important artifact in the history of medicine.
How Conjoined Twins Form
Chang and Eng’s fame put conjoined twinning on the map as a medical topic, but the question of how conjoined twins develop in the first place remains surprisingly contentious even today. Two competing theories have dominated the field for more than a century, and researchers still do not fully agree on which one is correct.
One view holds that conjoined twins arise from the incomplete splitting of a single embryo. Under this model, an embryo that would normally divide completely into identical twins fails to finish the job, leaving the two bodies partially connected. Proponents of this fission theory point out that all conjoined twins (except parasitic cases) are symmetrical, with the same body parts always joined to the corresponding parts on the other twin.4PubMed. The embryology of conjoined twins
The rival view, sometimes called the fusion theory, argues the opposite: two separate embryos that begin developing independently come into contact and partially merge. A large review of more than 1,200 cases arranged them into two uninterrupted series based on whether the twins were joined along the front or back of the body, and concluded that no version of the fission model can explain the specific sites where twins are found to be joined, the details of the union at those sites, or the limitation of conjunction to the observed areas.5Clinical Anatomy. Theoretical and analytical embryology of conjoined twins: Part I: Embryogenesis This analysis argued that fusion of two originally separate embryonic discs is the more convincing explanation.
The debate is more than academic, because the mechanism has implications for surgical planning and for understanding what organs conjoined twins are likely to share. If conjoined twinning results from incomplete fission, surgeons might expect a more predictable pattern of shared anatomy. If it results from secondary fusion, the anatomy at the junction could be more variable. In practice, modern imaging has made it possible to map shared organs in detail before any separation surgery, but the embryological question remains open. The fission theory still appears in many textbooks, while the fusion theory has gained support from detailed anatomical reviews.
Xiphopagus Twins After Chang and Eng
Chang and Eng were xiphopagus twins, and the category they represent has its own distinct medical profile. The 300-year review of xiphopagus cases found that about two-thirds of xiphopagus twins are female, following a broader pattern in conjoined twinning where female pairs outnumber male pairs by a substantial margin.6American Journal of Obstetrics and Gynecology. Xiphopagus conjoined twins: A 300-year review of the obstetric, morphopathologic, neonatal, and surgical parameters Chang and Eng, as a male pair, were in the minority.
The same review found a survival rate of about 53% across reported xiphopagus cases, a figure that includes both separated and unseparated twins across three centuries of medical history. The stillbirth rate was around 19%, and about a third of cases involved difficult deliveries. These numbers reflect eras with far less prenatal imaging and surgical capability than exists today. Modern outcomes for xiphopagus separation are considerably better when the twins do not share a heart, which is the case in most xiphopagus pairs. Chang and Eng’s shared liver bridge, while medically interesting, represented one of the less dangerous configurations of organ sharing.
Prenatal diagnosis was almost nonexistent in the historical record covered by that review, with only about 6% of cases detected before birth.7American Journal of Obstetrics and Gynecology. Xiphopagus conjoined twins: A 300-year review of the obstetric, morphopathologic, neonatal, and surgical parameters Today, conjoined twins are routinely identified on ultrasound during the first trimester, which changes the entire trajectory of medical planning. Families and surgical teams have months to study the anatomy of the connection, assess shared organs, and decide on a course of action.
Why the Phrase “Siamese Twins” Persists
Chang and Eng’s arrival in the English-speaking world in 1829 gave rise to a term that outlasted them by nearly two centuries.8PubMed. Exhibiting monstrosity: Chang and Eng, the ‘original’ Siamese twins “Siamese twins” became the default English phrase for any conjoined pair, and it remained the dominant term in both popular and medical usage well into the twentieth century. The medical community has largely shifted to “conjoined twins” as the preferred terminology, recognizing that “Siamese twins” collapses a medical condition into an ethnic label and perpetuates the association with spectacle and exoticism.
The persistence of the older term in everyday speech is partly a testament to how thoroughly Chang and Eng’s exhibition career embedded their image in Western culture. They appeared before presidents, were sketched and painted by prominent artists, and were written about in newspapers across the English-speaking world. For most nineteenth-century Americans and Europeans, the Bunker twins were the only conjoined pair they had ever heard of, and the phrase became shorthand for the condition itself. That kind of linguistic fossilization is hard to undo even when the reasons for changing it are clear.
The phrase also shows up in figurative use. Politicians, journalists, and commentators still occasionally describe two inseparable entities as “Siamese twins,” typically without thinking about the origin. This metaphorical usage has been criticized for reducing a real medical condition and real people to a rhetorical device, and style guides at major publications have increasingly discouraged it. Whether the term disappears entirely from colloquial English is an open question, but in medical and academic contexts, “conjoined twins” is now standard.
What Happened to Their Descendants
Chang and Eng’s combined 21 children produced a large extended family. By some genealogical estimates, the Bunker descendants now number well over a thousand people, scattered across the United States and beyond. Family reunions have been held periodically in the Mount Airy, North Carolina area, where the twins spent the latter part of their lives. Some descendants have spoken publicly about their ancestry, while others have preferred to keep it private.
The descendants are a living reminder that Chang and Eng’s lives were not defined solely by their conjoined status. They built families, raised children, farmed land, navigated a civil war, and dealt with financial ruin and recovery. The medical and exhibition dimensions of their story tend to dominate the popular imagination, but the domestic dimensions are just as revealing. Two men who could never be alone managed to sustain marriages, raise large families, and function as members of a rural community for decades. The coordination, compromise, and sheer patience that required is difficult to fully appreciate from the outside, and their descendants are the most tangible evidence that they managed it.