Timeline
Every guide, in its time.
Read across eras and regions, then open a guide to see the sources behind its dates. A shared date is a question to investigate, not evidence of contact.
8 of 57 guides in Across regions
5000–3000 BCE 1
- 4500–2500 BCE
How do you know a language that left no texts?
Proto-Indo-European: reconstructing a language nobody wrote.
Reconstructed; no attested texts · Across regions · Writing & languages
Thousands of years before writing reached Europe, a language ancestral to Sanskrit, Latin, and English was spoken. Learn what a reconstruction is and what it is not.
1–500 CE 1
- 100–1381 CE
How does a book travel across languages?
The Almagest: one book, four cities, a thousand years.
Alexandria, Baghdad, Toledo, Saragossa · Across regions · How knowledge travelled
Follow Ptolemy's astronomical treatise from second-century Alexandria through Arabic translation in Baghdad and Latin translation in Toledo to a dated copy made in Saragossa in 1381.
1000–1500 CE 3
- 1200–1599 CE
Why is a shared mistake better evidence than a shared design?
The Tusi couple in Greek: the Schemata of the Stars.
Maragha, Constantinople, and the Italian Renaissance · Across regions · How knowledge travelled
A Greek astronomical text carries a Persian lunar model and, with it, the same numerical error. Learn why a shared error is a stronger fingerprint than a shared diagram.
- 1300–1599 CE
How far can a resemblance be traced?
From Maragha to Copernicus: tracing a transmission claim.
Damascus, the Veneto, Cracow, Uppsala · Across regions · How knowledge travelled
Copernicus's planetary models resemble those of Ibn al-Shatir of Damascus. Follow a research case that grades each link in the chain, from verified fact to unsupported story.
- 1300–1599 CE
Is a matching model a copied model?
Mercury models: how close is close?
Damascus and Frombork · Across regions · Astronomy & calendars
Copernicus's mature Mercury model closely matches Ibn al-Shatir's. See which parts of that correspondence the research case grades as strong, and which common arguments it calls insufficient.
1500 CE onward 2
- 1580–1864 CE
Who built the star forts?
Star forts: what the construction records say.
Europe, the Americas, and Japan · Across regions · Kingdoms & monuments
Bastioned fortresses look alike from the air, which invites sweeping claims. Read five documented construction histories and see how different their dates and builders are.
- 1603–1739 CE
Does a name on a map prove a state?
Tartary on the map: what a label can and cannot tell you.
Northern and Central Asia on European maps · Across regions · Maps & geography
Three maps in the Library of Congress carry the label Tartary across northern Asia. Learn how a research record transcribes a map label without turning it into evidence of a political empire.
Not tied to one period 1
- Hypotheses about deep prehistory
Is there a mother of all languages?
How far back can language comparison reach?
Global · Across regions · Writing & languages
Nostratic, Borean, and Proto-World propose ancestors far deeper than Indo-European. Learn why the research record stores them as hypotheses with falling confidence rather than as ancestry.
Keep the habit
Dates are ranges. Read them that way.
Each guide names its period, its place, and the records that support them.
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