For most of human history, the birth of twins was never a neutral event. In some cultures, they were worshipped as gods; in others, they were killed as demons or treated as legal proof of adultery. The same biological occurrence produced radically different responses across civilizations, each one convinced its own reaction was the correct one. In ancient Rome, the prevailing legal and medical theory held that each baby resulted from a separate act of conception, meaning a woman who gave birth to twins was presumed to have slept with two different men.
Roman jurists and physicians debated twin paternity with striking seriousness, and the suspicion followed the mother socially and legally. The historian Tacitus called twin births a “rare felicity,” acknowledging they were not always treated as a scandal, but the doubt never fully disappeared. Rome also had a practical solution. The paterfamilias, the male head of the household, held the legal right to accept or reject any newborn.
In the case of twins, particularly in earlier Roman history, it was not uncommon to expose one of them—leaving the infant outside to die. This was regarded not as monstrous but as household management. The irony was that Rome’s founding myth celebrated twins. Romulus and Remus, sons of Mars and a Vestal Virgin, were abandoned in a basket on the Tiber River, saved by a wolf, and raised by a shepherd.
Romulus later killed Remus, and the city of Rome was founded on that bloodshed. The civilization that treated twin births as a legal problem built its identity around twin brothers, one of whom murdered the other. A very different logic governed parts of West Africa. Among the Igbo and Efik peoples of what is now southeastern Nigeria, twins were believed to be evil spirits wearing human skin—blood-sucking demons that would bring calamity and death to the community.
Both infants were routinely killed at birth, and in some cases the mother was killed as well or driven out of the community, on the grounds that a woman who produced twin demons must have done something to deserve it. This was not a fringe practice confined to one village. It was organized, ritualized, and spread across a wide geographic area for centuries. Documented evidence shows the practice continuing into the 20th century in isolated communities.
About 200 kilometers to the northwest, among the Yoruba people of Nigeria, Benin, and Togo, the exact opposite belief prevailed. The Yoruba have the highest twin birth rate on Earth—roughly 45 twin births per 1,000 pregnancies, about four times the global average. For them, twins were not demons but gods, known as the Ibeji, sacred beings protected by Shango, the god of thunder. Yoruba families celebrated twin births and commissioned carved wooden Ibeji sculptures to represent each child.
These figures were dressed in fine cloth, given offerings, and treated as living spiritual presences. If a twin died, the statue still had to be fed, clothed, and cared for, because neglecting it would bring misfortune upon the family. In other words, two neighboring groups, within a day’s travel of each other, responded to the same biological event in opposite ways—one killing twins, the other worshipping them. The Aztecs took a middle position that may have been the harshest of all.
Their patron deity of twins was Xolotl, a dog god associated with lightning, fire, and the underworld. Twins were regarded as dangerous omens, but instead of killing both infants, the Aztecs killed just one at birth. The reasoning behind which twin survived is not well documented. The Maya, by contrast, built one of their most enduring creation myths around twins.
In the Popol Vuh, the sacred text of the K’iche’ Maya, the hero twins Hunahpu and Xbalanque descend into Xibalba, the underworld, defeat the lords of death in a ball game, survive decapitation and other trials, and ascend to become the sun and moon. For the Maya, twins were not a problem to be managed; they were the reason the sky works. The oldest known twin burial on Earth dates back 31,000 years. Found at a Gravettian hunter-gatherer site in Krems-Wachtberg, Austria, the grave contained two newborn infants placed side by side, both coated in red ochre and adorned with carved ivory beads and perforated animal teeth.
One twin died at birth; the other survived about 50 days before dying. When the second twin died, the grave was reopened, carefully rearranged, and the second infant was laid beside the first. These people had no written language and no civilization in any modern sense, yet they reopened a grave to ensure two twins were buried together. They had no Roman law, no knowledge of Shango, and no system for deciding whether twins were sacred or cursed.
They simply knew these two belonged next to each other. The same biological event, in the same species, on the same planet, produced gods, demons, legal scandals, the founding myth of an empire, and a 31,000-year-old grave where a parent knelt in the dirt to lay one child beside its sibling. Every one of those responses was considered correct by the people who held it. None of them were crazy.
They were all attempts to explain something not understood by fitting it into a story that already made sense.
