The Blog

A library of stories and sources

From early cities and scripts to beliefs, science, and contested history. Pick a subject, read a guide, and open the material behind it.

Every guide links its sources. We mark what comes from a surviving object, what belongs to a tradition, and what remains a hypothesis.

96 of 96 source guides

Southwest Amazonia, Brazil Precolonial landscape; modeled peak around 100–300 CE

Amazon earthworks: 432 observed, thousands estimated

A laser survey found 432 earthworks. The thousands more in the headline are a model estimate, not newly observed sites.

Caves in Spain and Portugal Palaeolithic contexts; recovered DNA not directly dated to the art

Ancient DNA on a cave wall is not an artist's signature

Ancient human DNA survived on cave walls near paintings. Did it come from an artist or a later visitor? The evidence cannot tell us yet.

Boxgrove, West Sussex, England Middle Pleistocene, approximately 480,000 years ago

A 480,000-year-old tool and the evidence in its surface

A 480,000-year-old elephant bone carries marks of work. They help show how the tool was used, but cannot identify its maker.

Cis-Baikal, southeast Siberia Mid-Holocene, beginning about 5,500 years ago

Plague before farming cities: the Lake Baikal evidence

Ancient plague DNA was found near Lake Baikal among hunter-gatherer burials. Genomes point to two outbreaks, but not the number of deaths.

Bolivia and Tanzania; comparative global context Present-day samples informing a prehistoric migration model

Did gut microbes travel with us? A genomic model of deep migration

Gut microbes may carry traces of ancient human movement. Researchers reconstructed a possible route with a model; nobody observed that journey directly.

Egypt 196 BCE

The Rosetta Stone: one decree, three scripts

One decree was written in three scripts. How did comparison help people read Egyptian writing, and why was the stone not a ready-made dictionary?

Kingdom of Kush, Sudan c. 3rd century BCE – 5th century CE

We can sound out Meroitic. Why is the language still hard to understand?

Scholars can assign sounds to Meroitic signs, but many sentences still resist translation. Reading letters and understanding a language are different tasks.

Indus civilization sites, Pakistan and India c. 2600–1900 BCE

The Indus script is unread. Can we still learn what it was for?

The short inscriptions of the Indus civilization remain undeciphered. A study proposes how they were used, but that is not a translation.

Northwestern South Asia c. 1500–1000 BCE (composition horizon)

The Rig Veda: how old is a text first passed on by voice?

The hymns passed through an oral tradition before the surviving manuscripts were made. Composition, transmission, and copying have different dates.

Reconstructed; no attested texts c. 4500–2500 BCE (model-dependent)

Proto-Indo-European: how to reconstruct a language with no texts

No written record survives from the shared ancestor of Sanskrit, Latin, and English. Comparing languages can recover some features, but not its speakers’ exact words.

Eastern Europe 1st millennium BCE onward

When did Russian begin? There is no single birthday

The language changed over centuries, from shared Slavic ancestors to modern Russian. No one date marks its birth.

Global Hypotheses about deep prehistory

How far back can language comparison reach?

Proposed ancestors of very old language families reach beyond surviving texts. Where can comparison still test a claim, and where does it become a hypothesis?

Northwestern Europe From Proto-Germanic, c. 500 BCE, onward

English and German: the ancestor they share

They sound different today, but share a West Germanic ancestor. Their relationship lies in how words changed, not in a single date when either language began.

Piauí, northeastern Brazil Rock art; disputed early occupation claims

Serra da Capivara: rock art and the oldest-dates debate

Hundreds of rock-art sites survive at Brazil’s Serra da Capivara. The earliest proposed dates for people in the area remain disputed.

Arica and Parinacota, northern Chile 5450–890 BCE

Chinchorro: mummies thousands of years before Egypt’s

People on the Atacama coast preserved the dead long before ancient Egyptians did. The practice lasted for centuries; it was not one event.

Supe Valley, Peru c. 3000–1800 BCE

Caral: a wider map of early urban life

Caral shows that early urban life was not confined to one region. A shared timeline lets us compare societies without inventing contact between them.

Şanlıurfa, southeastern Türkiye 9600–8200 BCE

Göbekli Tepe: monuments raised before farming towns

At Göbekli Tepe, people raised carved stone enclosures before farming towns appeared. How do archaeologists date a place that changed over time?

Southern Mesopotamia, Iraq c. 5300–4100 BCE

Ubaid: the villages before the first cities

Ubaid settlements came before Mesopotamia’s large cities. Two published timelines for the period differ, and averaging them would hide the disagreement.

Southern Mesopotamia, Iraq 4000–3100 BCE

Uruk: how one of the first cities grew

Large buildings, administration, and early writing reveal Uruk’s growth. But a long historical period rarely has an exact start date.

Indus and Ghaggar-Hakra basins, Pakistan and India 2600–1900 BCE

The Indus cities: how can we tell how old they are?

Without lists of kings, archaeologists date Indus cities through changing objects and radiocarbon samples. What can each kind of evidence tell us?

Kachi plain, Balochistan, Pakistan c. 5200–4700 BCE (Neolithic cemetery, 2025 model)

Mehrgarh: why new dates change a cemetery’s history

Tooth-enamel measurements published in 2025 suggest a later date for Mehrgarh’s cemetery. They do not automatically redate every layer of the settlement.

Murghab delta, Turkmenistan c. 2250–1700 BCE (alternative model from c. 2400 BCE)

Gonur Depe and the Oxus civilization: a Bronze Age world with two clocks

The largest site of the Oxus civilization has two published timelines. Compare their evidence before assigning a single date to the whole culture.

Northern Sudan, Middle Nile c. 2450–1500 BCE

Kerma: a kingdom of its own beside Egypt

Kerma grew into a powerful Kushite centre south of Egypt. Which finds support the case for an independent state?

Konya plain, central Anatolia, Türkiye c. 7400–6200 BCE (Eastern mound)

Çatalhöyük: a town without streets

At Çatalhöyük, houses stood so close that residents entered through roofs. Two mounds and many layers show how the settlement changed.

Jordan Valley, Palestine c. 10,500 BCE onward

Jericho: eleven thousand years in one mound

Jericho preserves traces of thousands of years beside a spring. The oldest date for the mound cannot simply be assigned to its later walls.

Upper Egypt and the Nile Valley c. 4000–2686 BCE

From Naqada to the first dynasties

Over a thousand years, Upper Egyptian communities became the kingdom of the first dynasties. Objects and radiocarbon dates reveal different parts of the change.

Diyala region and southern Mesopotamia, Iraq 2900–2350 BCE

Sumer: how scholars divide its early history

The Square Temple at Tell Asmar helped define the Early Dynastic period. The boundaries of its stages remain debated.

Meroë, Nuri, Gebel Barkal, and Sedeinga, Sudan c. 900 BCE – 350 CE

The pyramids of Sudan: counting what survives

More pyramidal structures survive in Sudan than in Egypt. The total depends on what you count and how many have already disappeared.

Gebel Barkal and the Napatan region, Sudan c. 900–270 BCE

Napata: the kingdom that ruled Egypt from the south

Kushite rulers governed Egypt as the Twenty-fifth Dynasty. Follow the story from Gebel Barkal to pharaonic power without blending the dates of each stage.

Bekaa Valley, Lebanon Roman sanctuary over earlier, undated remains

Baalbek: what is older, the temple or the remains below it?

Earlier remains lie beneath the Roman temple. Their age does not make every part of the great structure above them equally old.

Europe, the Americas, and Japan 1580–1864 CE

Star forts: what the construction records say

Fortresses in different countries share a star-like shape. Five documented building histories let us check who built each one and when.

Ancash, Peru 1500–300 BCE

Chavín: a ceremonial centre before the Andean states

Chavín de Huántar gave its name to a style found across the Andes. The site’s building phases and the style’s spread have different dates.

Coastal plain of southern Peru 500 BCE – 500 CE

The Nasca lines: a date cannot explain their purpose

The vast drawings at Nasca and Palpa were made over centuries. A date places each one in history, but does not explain by itself why it was made.

Lake Titicaca basin, Bolivia 400–900 CE

Tiwanaku: when did the city thrive, and when was it built?

Tiwanaku became a centre on the high Andean plateau. Its peak of influence is not automatically the date of every building.

Neva delta, Russia 1611–1740 CE

St Petersburg before 1703: what stood on the site?

Peter I’s city plan, an earlier Swedish fortress, and the stages of the Peter and Paul Fortress appear in different records. Together they give a checkable history of the place.

Mesopotamia c. 1800 BCE

Plimpton 322: a Babylonian table and its interpreters

Plimpton 322 is a clay tablet filled with columns of numbers. We can read them, but scholars still debate why the table was made.

Thebes, Upper Egypt 1550 BCE

The Rhind Papyrus: a scribe's handbook of problems

The Rhind Papyrus contains 84 mathematical problems. The date of the surviving roll may differ from the age of the problems it records.

Zhangjiashan, Hubei, China Western Han, tomb closed by 186 BCE

Writings on Reckoning: a tomb manuscript and a known classic

The bamboo manuscript Suan shu shu was found in a Han tomb. It helps us test the history of the Nine Chapters, known through later copies.

Kouyunjik, Nineveh, Iraq 7th century BCE

K.2069: a reciprocal table from the library at Nineveh

Tablet K.2069 shows how reciprocal numbers were written in Nineveh’s base-60 system. The tablet’s age is not the date when the method was invented.

Syracuse, Sicily 287–212 BCE

Archimedes: what survives of his works

Archimedes’ works reached us in copies made many centuries later. Understanding them means keeping the author, the work, and the manuscript apart.

Mesopotamia (provenance unknown) Old Babylonian period

YBC 7289: the square root of two on a school tablet

A small Babylonian tablet shows a square and an approximation of the square root of two. Try reading its number the way the scribe wrote it.

Mesopotamia 1000–500 BCE

MUL.APIN: a Babylonian compendium of the sky

The MUL.APIN tablet preserves Babylonian knowledge of the sky. The surviving copy’s date does not tell us when that tradition began.

Babylon 652–651 BCE

Astronomical Diaries: a dated record of the Babylonian sky

Babylonian scribes left dated observations of the sky. Tablet BM 32312 helps separate a recorded event from a later explanation of it.

Damascus and Frombork 14th–16th centuries CE

Copernicus and Ibn al-Shatir: how close are their Mercury models?

Two models of Mercury’s movement look strikingly alike. Which matches suggest knowledge was passed on, and which leave its route unproven?

South Asia 499 CE (traditional scholarly date)

The Āryabhaṭīya: dating a work and its witnesses

The Āryabhaṭīya is usually dated to 499 CE, but surviving copies are later. A scholarly edition helps keep the work’s date apart from the manuscripts’ dates.

Thebes, Egypt late 16th century BCE

Papyrus Ebers: a medical scroll from the end of the 16th century BCE

Papyrus Ebers brings remedies, spoken formulas, and ideas about the body together. The scroll and its edition show how these kinds of knowledge sat side by side in ancient Egypt.

Greek world and Byzantium Ancient texts in Byzantine manuscripts

Hippocrates and Dioscorides: ancient medicine in later manuscripts

Greek medical works survive through Byzantine manuscripts. A copy’s date tells us when it was made, not when the text first appeared.

Egypt (find spot unknown) 18th Dynasty, c. reigns of Amenhotep I to Amenhotep II

Papyrus Berlin 3027: spells and remedies for mother and child

An Eighteenth Dynasty papyrus places remedies and spells for mothers and children together. Does our modern line between treatment and ritual fit this text?

Eastern Mediterranean Ancient Greek world

Antikythera: how much can a fragment reveal?

Only fragments of the Antikythera mechanism survive. What can we see on them, and what has been added in a scholarly reconstruction?

Jazira and Yemen 1235–1291 CE

Two thirteenth-century astrolabes: what does an inscription prove?

Compare instruments in London and New York. A dated inscription, a museum record, and a surviving treatise answer different questions about their history.

Roman Egypt late 3rd century CE

Two ancient recipe papyri: craft or alchemy?

The Leiden and Stockholm papyri give recipes for metals, dyes, and stones. Similar subjects do not by themselves prove a direct link between the texts.

Egypt and Byzantium 1st–7th centuries CE

Who wrote the alchemical text? Three different answers

Zosimos, Stephanos, and Pseudo-Democritus present three different authorship stories. Before comparing recipes, ask whose name each text carries and why.

Alexandria, Baghdad, Toledo, Saragossa 2nd century CE – 1381 CE

The Almagest: one book, four cities, a thousand years

Ptolemy’s astronomy moved through Arabic and Latin translations. A manuscript from Zaragoza marks one stop on a journey spanning more than a thousand years.

Abbasid Baghdad, later Béziers 9th century CE – 1199 CE

Hunayn ibn Ishaq: why translate Galen twice?

In the ninth century, Hunayn translated Galen into Syriac and Arabic for different readers. The Arabic version may preserve material lost in Greek.

Damascus, the Veneto, Cracow, Uppsala 14th–16th centuries CE

From Maragha to Copernicus: tracing a transmission claim

Copernicus’s planetary models resemble earlier work by astronomers in the Islamic world. Which steps in the possible transmission are documented, and which are missing?

Graeco-Roman Egypt Late antiquity

Hermetic texts: ancient wisdom or later writing?

The Hermetic treatises present themselves as teachings of an ancient Egyptian sage. Each text needs its own dating; its title is not proof of age.

Paris and Toledo 15th century CE

Euclid in Latin: a fifteenth-century witness

A fifteenth-century Paris manuscript preserves Euclid in Latin, translated from Arabic. The copy, the translation, and Euclid’s life belong to different dates.

Cracow, Padua, and Uppsala 14th–16th centuries CE

Bianchini’s tables in Copernicus’s hand: what is proven?

Copernicus copied planetary latitude tables in his own hand. It is a strong find, but does not by itself settle every question about how he used them.

Maragha, Constantinople, and the Italian Renaissance 13th–16th centuries CE

The Tusi couple in Greek: why a shared error matters

A Greek text preserves a Persian Moon model and repeats a numerical error. That shared mistake is stronger evidence of a textual link than a similar drawing.

Venice, Padua, and Mantua c. 1460–1540 CE

How astronomy reached Italy: three traces

A library, a travelling scholar, and a Mantua notebook reveal three routes for astronomical knowledge. Two important links in that story remain missing.

Damascus and Oxford c. 1366 CE and after

Ibn al-Shatir: which manuscript preserves the relevant theory?

His fourteenth-century planetary theory survives in several manuscripts. His separate work on the astrolabe does not alone prove that his Mercury model reached Copernicus.

Northern and Central Asia on European maps 1603–1739 CE

Tartary on an old map: a name or an empire?

Three Library of Congress maps label northern Asia Tartary. That historical name is not evidence of a single empire ruling the whole region.

Nubian Desert, southern Egypt Neolithic; chronology depends on the dated context

Nabta Playa: stones, sky, and an unproven link to Egypt

Stone monuments in southern Egypt are linked to ritual and sky-watching. A route from them to later Nile Valley traditions has not been traced.

Mesopotamia Early Mesopotamian cultural horizons

Mesopotamian gods: why place and date matter

Similar images appear in different ancient traditions. To test a link, first find where, when, and in which source each one appears.

Iranian world Origin chronology disputed; later textual and reception layers

Zoroaster: why one story has several dates

Traditions about the founder, the writing of sacred texts, and surviving copies belong to different times. They cannot be reduced to one birth year.

Iran, Babylonia, and the southern Levant Achaemenid and later contact horizons

Persians and Jews: when do similar ideas show influence?

The two peoples lived near each other and had contact. A claim that a specific religious idea passed between them still needs texts, dates, and alternative explanations.

Yehud and the southern Levant Persian-period context; composition models remain debated

The Pentateuch: how texts took shape in an age of empires

The Pentateuch was assembled and passed on in a changing historical world. Scholars disagree about the role imperial settings played in that history.

North India Early Buddhist intellectual milieu; founder chronology debated

Early Buddhism: what questions were other schools asking?

Ancient Indian thinkers debated suffering, actions, and liberation. That setting helps us understand the Buddha’s teaching without blending it with later accounts of his life.

Jewish manuscript traditions Early medieval attestation and later reception; edition 2004

Sefer Yetzirah: why do the manuscripts differ?

This short book survives in several versions. Compare the manuscripts before speaking of one fixed “original” text.

Jewish mystical textual traditions Medieval textual tradition; cited translation 1989

The Bahir: why one translation is not the whole story

A translation helps you begin, but it depends on a Hebrew edition and a history of manuscripts. See what text lies behind the familiar wording.

Jewish mystical traditions Medieval manuscript horizons and later editions

The Zohar: one book or a collection of texts?

The Zohar reached us as a layered written tradition. Translation opens its meaning; manuscripts reveal the history of its parts.

Jewish manuscript traditions Late antique and medieval textual layers; synopsis 1981

Hekhalot: how to compare stories of ascent to heaven

Related manuscripts tell stories of heavenly ascent in different ways. Comparison reveals what they share without turning them into one book.

Safed and Jewish mystical traditions Sixteenth-century setting; cited study 2003

Isaac Luria: how ideas changed within a community

Mystical ideas lived in people and rituals as well as texts. The community’s history helps explain the development of Lurianic Kabbalah.

Ottoman and Jewish communities 1626–1676; modern scholarly editions

Sabbatai Sevi: how to study a messianic movement

Followers’ belief is part of the movement’s history, not proof of its prophecies. Dated evidence helps trace how it grew and changed.

Jewish intellectual history Modern scholarship on ancient and medieval traditions

Jewish mysticism: why do scholars tell different histories?

Different studies start with different texts and periods. Compare their sources before accepting a single map of the past.

Mediterranean and later alchemical traditions Ancient traditions through later reception

Alchemy over the centuries: what changed with the recipes?

Alchemy brought together work with materials, written traditions, and spiritual readings. To link them, we need the date and setting of each source.

Byzantine textual traditions Byzantine reception of earlier alchemical material

Byzantine alchemy: how recipes were kept and changed

Collections and commentaries did more than copy older knowledge. They show how Byzantine readers organized and understood alchemical texts.

European intellectual and religious traditions Early modern and nineteenth-century reception

Spiritual alchemy: when did new readings appear?

Later spiritual interpretations deserve study in their own right. They cannot be assigned to ancient recipes and experiments without evidence.

Modern European intellectual history Modern occult and scientific reception

Modern alchemy: why did old ideas return?

Interest in alchemy did not end with ancient craftspeople. Modern sources tell a separate story of its revival in occult movements.

Early modern England Newton’s working period; cited scholarship 2016

Newton’s alchemy: what did he write, and what did he do?

Newton’s notebooks mix ideas with procedures for working with materials. A study separates a recorded recipe from an experiment we can confirm.

United States 1972–1974; later archival release

Watergate: what does one recorded conversation tell us?

A familiar event name leads to specific archival tapes. Date, participants, and recording number help test a precise claim.

United States 1977 hearing on earlier activities

MKULTRA: what do the hearing and official reply tell us?

A government hearing and an agency response answer different questions. Compare them and note which records have not survived.

United States Twentieth-century programs and 1970s review

COINTELPRO: what do the program’s records show?

Archives and a congressional inquiry document the program. Each specific episode still needs its own supporting record.

United States, Iran, and Nicaragua 1980s events and subsequent investigation

Iran–Contra: which records reconstruct the case?

An archival finding aid leads through the investigation’s records. Dates and the purpose of each document help build a checkable sequence.

Roswell, New Mexico, United States 1947 event; 1990s records searches and reports

Roswell: what did the official archives contain?

Agencies searched their records and later issued reports. Compare their conclusions without treating a missing document as proof of any theory.

European publication and later international reception Nineteenth- and twentieth-century textual history

The Protocols: how an antisemitic forgery was exposed

Documents trace the creation and spread of an antisemitic forgery. Comparing texts reveals the evidence that exposed it.

United States Cold War activities and 1970s investigation

The CIA and the media: what do documents confirm?

One familiar label is often used for different actions. Official inquiries and agency rules let us check each claim separately.

Jebel Irhoud, Morocco Middle Pleistocene fossil context

Jebel Irhoud: what do the fossils say about early humans?

Fossils help us study human origins, but one set of remains does not describe a whole population. A wider account needs other evidence.

Africa Deep human population history; study 2023

Human origins: why does the model include several groups?

A genetic model describes connected ancestral groups with gene flow between them. It is a testable proposal, not a story about one isolated population.

Human populations worldwide Present-day genomic variation

Human genomes: what do we share and where do we differ?

Most human DNA is shared. A research institute’s introduction helps explain differences without turning genetic comparison into a label for a person.

Nineveh and Mesopotamian textual traditions Neo-Assyrian tablet witness to Gilgamesh Tablet XI

Gilgamesh: what does one tablet say about the flood?

Before comparing flood stories, look at an identified museum tablet. Its date and words set the bounds of the comparison.

Thebes, Egypt New Kingdom manuscript context

The Book of the Dead: what is in Ani’s papyrus?

One surviving manuscript joins funerary texts and images. It helps us study ancient beliefs without treating every copy as the same book.

Chinese textual traditions Early Chinese tradition and later textual transmission

Dao De Jing: which text should you start with?

A digital edition opens the Chinese text. Compare it with a translation to see how each word choice can shift a reader’s understanding.

Chinese textual traditions Early Chinese philosophy and later textual transmission

Zhuangzi: how does a story become a philosophical question?

Read the whole story, then compare a translation. It helps separate the written text, its possible meaning, and later interpretations.

Chinese textual traditions Early Chinese divination and later commentary traditions

Yijing: where does the text end and commentary begin?

The Book of Changes has layers from different periods. Keep the early text apart from later commentaries and uses.

Babylonia; monument found at Susa Old Babylonian royal and legal context

Hammurabi’s laws: what can a stone monument tell us?

The inscription presents rules and an image of royal authority. To learn how real cases were decided, we also need records of legal practice.