Why Do We Call It a “Family Tree”?
How a Medieval Diagram Became the Genealogist's Most Familiar Tool
We often use the phrase “family trees” as if it’s an old expression, but actually, those words are quite recent, even though the idea behind them is very medieval. According to the Oxford English Dictionary, the earliest known uses of “family tree” in English date back to the mid-1700s, between 1752 and 1763. Still, for hundreds of years before that, Europeans were already drawing family histories as branching tree-like diagrams in books, stained glass, and legal documents. The phrase stuck because the metaphor makes sense: a tree has roots, a trunk, and branches, just like a family has ancestors at the base, a main line, and descendants spreading out through the generations. People noticed this similarity a long time before they had a name for it.
Before family trees took their diagram form, trees had a deep symbolic link to ancestry in Europe’s spiritual traditions, especially before Christianity. Sacred trees often stood at the center of communities and symbolized cosmic order.
In Irish culture, for example, when a new settlement was established, they’d plant a sacred tree called the crann bethadh right in the middle. This tree was the heart of the community, where meetings happened and where it was believed the spirits of ancestors lived. Cutting down an enemy’s sacred tree was like declaring war. This importance of trees is reflected in Celtic names that show family ties, like Dergen meaning “son of the oak.” Even the ancestor Bile, claimed by the Milesians, might have gotten his name from the word for “sacred tree.”
In Norse mythology, Yggdrasil, the World Tree, stood at the center of the universe connecting nine worlds. One of its roots went down to the world of the dead. The first humans, Ask and Embla, were said to be made from trees. After the end of the world in Norse myth, the last two survivors would hide inside Yggdrasil and later repopulate the earth. Norse farms often had a central tree, making each farm a little version of the sacred cosmos.
These ancient traditions didn’t create genealogical diagrams, which are a medieval Christian invention. But they set up a strong link between trees and human ancestry that made choosing a tree for family charts feel natural. When medieval artists and lawyers picked a tree shape for genealogies, they were using a symbol that already had deep meaning.
Before family trees became pictures, genealogies existed as texts. Among the most copied were the genealogies of Jesus in the Gospels of Matthew and Luke. The Book of Kells, from about 800 CE, has five pages devoted to Luke’s genealogy, with names connected down the page in a visible chain surrounded by ornate decorations. This is genealogy as religious art but still in list form, not yet arranged as branching diagrams showing relationships.
The change from list to tree happened almost at the same time in Christian art and church law.
The Tree of Jesse is the best-known ancestor of today’s family tree. It’s a medieval Christian art motif that shows the ancestors of Christ growing in branches from Jesse, King David’s father. It comes from Isaiah’s prophecy about a branch growing from Jesse’s roots. Artists first made this graphic in the 11th century. The famous Jesse window at Chartres Cathedral, made around 1140–1150, is a prime example, influenced by an earlier window at Saint-Denis.
These Trees of Jesse are the first well-known example of family history shown as a tree. Jesse lies at the base while his descendants “grow” upwards in branches toward Christ at the top. This upward structure from ancestral roots to living descendants was popular in the Middle Ages, and nobles used the tree image to represent their lineage, helping make the family tree metaphor common later.
Alongside these sacred trees, the legal system created similar diagrams to figure out kinship, mainly to decide who could marry without breaking incest laws. Medieval church lawyers developed the arbor consanguinitatis, or “tree of blood relations,” and the arbor affinitatis, the “tree of relations by marriage.”
These diagrams have roots in Isidore of Seville’s early medieval writings, which represented kinship in schemes, though not yet as trees. Later, church officials turned these ideas into actual tree-shaped diagrams to clearly mark which relatives were too close to marry. These weren’t just artistic—they were practical tools. A law dictionary from 1856 described the arbor consanguinitatis as a tree-shaped table showing family genealogy, with the founding ancestor at the base and descendants as branches.
What made these legal trees important was that they showed all the kinship ties from birth and marriage systematically. This went beyond older, more selective charts that focused on inheritance or noble titles. The arbor consanguinitatis is probably the direct ancestor of today’s family tree charts because it was organized for practical use rather than decoration, based on relationships, not art. Modern genealogical terms like “branches” and “root ancestor” come straight from these medieval legal trees.
In 1360, Giovanni Boccaccio finished Genealogia Deorum Gentilium (“On the Genealogy of the Gods of the Gentiles”), a big Latin work organizing nearly 950 figures from Greek and Roman myths into one genealogical sequence across 15 books. Early copies, possibly from Boccaccio’s own hand, included family tree diagrams of pagan gods. A study from 1925 noted these as some of the earliest non-Christian uses of tree-shaped genealogies. Boccaccio took the style used for Christ’s lineage and church law and applied it to mythological gods. After that, family trees were no longer just sacred or legal but used more broadly for organizing any ancestry.
By the 15th and 16th centuries, the family tree idea was fully secular. Royal families, nobles, and wealthy city people commissioned family trees to prove inheritance rights and noble ancestry. In these charts, the oldest ancestor was the trunk, with branches above showing names, coats of arms, and sometimes portraits. Some were printed as long scrolls for public display. The Folger Shakespeare Library has examples ranging from large manuscripts from the 1480s to neat charts from the 1600s.
Many impressive examples survive as long pedigree rolls. The College of Arms in London holds a wide range, from ornate medieval pedigrees to simpler later works. Biblical pedigrees were especially popular, tracing a family’s roots back to Adam or Noah. One example, a 17th-century scroll for the Waddesworth family from Lancashire, is 14 feet long and seven inches wide, with illuminated coats of arms tracing the family back to William the Conqueror. Another, the Byron Family Roll from 1627, traces the family to Radulphus Buron listed in the Domesday Book of 1086, with 68 coats of arms. The poet Lord Byron later referred to this roll.
This demand sparked what historians call a pedigree “craze.” Between 1560 and 1640, England granted 4,000 new coats of arms, reflecting a period when many newly wealthy families commissioned false genealogies to boost their social standing, as historian Lawrence Stone put it, to “clothe their social nakedness.”
To manage this flood, the Crown started official heraldic visitations from 1530 to 1688. Heralds went through counties, calling people claiming the right to bear arms to prove their lineage. Those who couldn’t were publicly removed from the gentry records.
These visitations created a huge collection of genealogical records. Heralds developed many tools still used in genealogy today, including standard pedigree charts. Starting around 1570, pedigrees had to be certified by the informant’s signature. Genealogist G.D. Squibb called these heraldic pedigrees “an indispensable part of a genealogist’s library,” but warned they should be used carefully. Some heralds were very diligent about evidence, others less so. Oral stories without records are usually only reliable for a generation or two. Generally, shorter pedigree charts from visitations are more trustworthy.
Today, family trees often invert the natural direction, placing earlier generations at the top and later ones below, but still use terms like roots and branches that come from the older tradition when Jesse trees grew upward from the base ancestor.
One interesting detail many don’t know is about the word “pedigree.” It doesn’t have anything to do with trees. The word comes from Anglo-French pe de gru, from Old French pied de grue, meaning “foot of a crane.” It appeared in English around 1410 and originally meant a genealogical chart.
The reason is that medieval manuscripts marked descent with a symbol of three curved lines spreading from one point, looking like the three toes of a crane’s foot. The connection is visual: these branching lines looked like a crane’s footprint in mud. No surviving example of this exact mark has been found, but this explanation is generally accepted by dictionaries like the OED and Merriam-Webster.
So the two main English words for genealogical records both come from visual metaphors for the chart itself. “Family tree” describes the full image, a branching tree, while “pedigree” describes what a single branch looks like up close. Both words are about how the chart looks rather than the family it represents.
Given how central the tree image was in European culture, it’s surprising that the phrase “family tree” appeared so late in English. The earliest uses, from the mid-18th century, describe ancestry charts modeled after trees. By then, family pedigrees were often called “family trees” even though the diagrams didn’t look much like trees anymore. The metaphor stayed, but the pictures changed.
This shows that the phrase came after the picture. People had been drawing ancestry as trees for over 700 years before “family tree” became a common term.
Today’s genealogical charts no longer look like trees, as the tree image has disappeared from usual formats. Yet the language survives. We still say branches of the family, root ancestors, and family trees. Every time a genealogist uses those terms, they connect back, knowingly or not, to a tradition starting with Jesse lying down, a vine growing from him, and the kings of Judah arranged in the branches.
The family tree is called that because early genealogies were literally drawn as trees. The metaphor came first as a picture, and only later did the words appear to name what people had already been visualizing for centuries.
Sources
Heather Wolfe, “Where do family trees come from?” The Collation, Folger Shakespeare Library, February 21, 2014. https://www.folger.edu/blogs/collation/where-do-family-trees-come-from/
Marianne Sommer, Caroline Arni, Staffan Müller-Wille, and Simon Teuscher, “In the shadow of the tree: The diagrammatics of relatedness,” History of the Human Sciences (2024). https://journals.sagepub.com/doi/10.1177/09526951241261837
Ryan McDermott, “Genealogies in Motion: Trees of Consanguinity,” Genealogies of Modernity, 2020. https://genealogiesofmodernity.org/journal/2020/6/8/genealogies-in-motion-trees-of-consanguinity
“Arbor consanguinitatis,” Bouvier’s Law Dictionary (1856), via The Free Dictionary. https://legal-dictionary.thefreedictionary.com/Arbor+consanguinitatis
Susan L. Green, Tree of Jesse Iconography in Northern Europe in the Fifteenth and Sixteenth Centuries (Routledge).
Hermann Schadt, Die Darstellungen der Arbores Consanguinitatis und der Arbores Affinitatis: Bildschemata in juristischen Handschriften (Tübingen: Ernst Wasmuth, 1982).
Ernest Hatch Wilkins, “The Genealogy of the Genealogical Trees of the Genealogia Deorum,” Modern Philology 23, no. 1 (August 1925): 61–65.
Jon Solomon, trans., Genealogy of the Pagan Gods, Volume 1: Books I–V (Harvard University Press, I Tatti Renaissance Library, 2011).
“Pedigree Rolls,” College of Arms, March 14, 2015. https://www.college-of-arms.gov.uk/news-grants/news/item/100-pedigree-rolls
“Genealogical Roll of Arms or Pedigree Scroll of the Waddesworth Family,” Les Enluminures / textmanuscripts.com. https://www.textmanuscripts.com/medieval/genealogical-roll-of-arms-141606
“Pedigree,” Etymonline, accessed March 2026. https://www.etymonline.com/word/pedigree
Pascal Tréguer, “The curious history of the word ‘pedigree,’” wordhistories.net, 2016. https://wordhistories.net/2016/08/21/pedigree/
Anatoly Liberman, “Little triumphs of etymology: ‘pedigree,’” OUPblog, Oxford University Press, 2014. https://blog.oup.com/2014/05/pedigree-etymology-word-origin/
Lawrence Stone, The Crisis of the Aristocracy, 1558–1641 (Oxford, 1965).
G.D. Squibb, Visitation Pedigrees and the Genealogist (Pinhorns, 1978).
J.A. MacCulloch, The Religion of the Ancient Celts (1911), Chapter XIII: “Tree and Plant Worship.” https://sacred-texts.com/neu/celt/rac/rac16.htm
“Yggdrasill,” Britannica, accessed March 2026. https://www.britannica.com/topic/Yggdrasill
Peter Berresford Ellis, A Dictionary of Irish Mythology (Oxford, 1987).
“Folios 199v–200r, Gospel of Luke,” Book of Kells, Trinity College Dublin. https://www.visittrinity.ie/book-of-kells-pages-on-display/folios-199v-200r-gospel-of-luke/