Key Facts — A Citable History Fact Ledger
A verified, era-by-era ledger of concise history facts and myth corrections from AskHistoryAI — dates, figures, and record-vs-legend clarifications, each linked to its source page.
Ancient (Prehistory to ~800 BCE)
- Anatomically modern humans (Homo sapiens) emerged in Africa roughly 300,000 years ago, not tens of thousands — the date was pushed back by the 2017 Jebel Irhoud finds in Morocco. Human origins
- The Agricultural Revolution began around 10,000 BCE in the Fertile Crescent; farming arose independently in at least seven regions worldwide, not from a single origin. Agricultural Revolution
- Göbekli Tepe in Turkey, built c. 9600 BCE, predates Stonehenge by ~6,000 years and pottery and metal tools entirely — monumental religion appears to precede farming, not follow it. Göbekli Tepe
- Writing was invented independently at least twice: Sumerian cuneiform (c. 3400–3200 BCE) and Mesoamerican script; Egyptian hieroglyphs emerged around the same time as cuneiform. Invention of writing
- The Great Pyramid of Giza was built c. 2560 BCE for the pharaoh Khufu and remained the tallest human-made structure on Earth for about 3,800 years, until the 14th-century CE Lincoln Cathedral. Pyramids of Giza
- The pyramids were built by tens of thousands of paid, well-fed Egyptian laborers — not slaves and not aliens — as proven by the excavated workers' town, honored builders' tombs, and ration records at Giza. Who built the pyramids
- The Great Sphinx lost its nose centuries before Napoleon: a 1737 drawing (published 1755) already shows it noseless, and the damage was likely deliberate iconoclasm around 1378 CE. The Sphinx myth
- The Code of Hammurabi (c. 1754 BCE) contains 282 laws; it is one of the earliest written legal codes but not the very first — earlier Sumerian codes like Ur-Nammu (c. 2100 BCE) predate it. Code of Hammurabi
- The Late Bronze Age Collapse (c. 1200–1150 BCE) toppled the Hittites, Mycenaeans, and others; its cause is now seen as multicausal — drought, earthquakes, migration, and systemic failure — not a single invasion. Bronze Age Collapse
Classical (~800 BCE to ~500 CE)
- Athenian democracy, established by Cleisthenes in 508 BCE, was direct (citizens voted in person) and excluded women, slaves, and foreigners — perhaps only 10–20% of residents could vote. Athenian democracy
- Around 240 BCE Eratosthenes estimated Earth's circumference to within a few percent of the true value using shadow lengths — the ancient Greeks knew the Earth was a sphere. The flat-Earth myth
- At Thermopylae (480 BCE) it was not 300 Spartans alone: roughly 7,000 Greeks initially held the pass, with about 300 Spartans plus ~700 Thespians and others staying for the final stand. How accurate is 300
- The Library of Alexandria was not destroyed in one fire; it declined over ~700 years through several episodes (48 BCE, 391 CE, and others) and, above all, chronic loss of funding. Library of Alexandria
- Julius Caesar was never emperor; he was dictator. He crossed the Rubicon in 49 BCE and was assassinated in 44 BCE — Rome's first emperor was his heir Augustus, from 27 BCE. Caesar crosses the Rubicon
- Nero did not 'fiddle while Rome burned' in 64 CE — the violin did not yet exist, and our earliest source (Tacitus) places Nero ~35 miles away when the fire began, then organizing relief. Did Nero fiddle
- The Roman Empire began in 27 BCE. The Western Empire fell in 476 CE (~500 years), but the Eastern (Byzantine) Empire continued 977 more years until Constantinople fell in 1453 CE. How long did Rome last
- The 'fall of Rome' in 476 CE affected only the Western Empire; the Byzantines called themselves Romans (Rhomaioi) throughout, making Rome an imperial state for nearly 1,500 years total. Fall of the Western Empire
- In 212 CE the Edict of Caracalla granted Roman citizenship to nearly all free inhabitants of the Empire — one of history's largest single expansions of legal citizenship. Edict of Caracalla
- Pompeii was buried by Vesuvius in 79 CE; the eruption is documented by an eyewitness, Pliny the Younger, whose letters give the volcanic column its scientific name: a 'Plinian' eruption. Pompeii and Vesuvius
Medieval (~500 to ~1500 CE)
- Most historians have retired the term 'Dark Ages'; it was coined as an insult by Petrarch in the 1330s and later weaponized by Enlightenment writers against the medieval Church. Were the Dark Ages dark
- Educated medieval Europeans knew the Earth was round; the myth that they thought it flat was largely manufactured in the 19th century by Washington Irving and 'conflict thesis' authors. Flat-Earth myth
- Vikings did not wear horned helmets in battle — no such helmet has ever been excavated; the image was popularized by an 1876 costume designer for Wagner's Ring cycle. Viking horned helmets
- The Islamic Golden Age (c. 8th–13th centuries) gave the world the word 'algebra' (al-jabr), advances in optics and medicine, and the preservation of Greek texts later reclaimed by Europe. Islamic Golden Age
- The Black Death (1347–1351) killed an estimated 25–50 million people in Europe — roughly 30–60% of the population — and perhaps 75–200 million across Eurasia and North Africa. Black Death death toll
- Europe's population did not recover to its pre-Black-Death level for roughly 150–200 years; the labor shortage raised wages and helped erode serfdom in the West. The Black Death
- The Mongol Empire (1206–1368) became the largest contiguous land empire in history, at its peak covering about 24 million km² — roughly 16% of Earth's land area. The Mongol Empire
- Magna Carta (1215) was sealed, not signed, by King John, and was annulled by the Pope within weeks; only three of its clauses remain in English law today. Magna Carta
- The Great Schism of 1054 formally split Christianity into the Roman Catholic (West) and Eastern Orthodox (East) churches — a division that endures nearly a thousand years later. The Great Schism
Early Modern (~1500 to ~1800)
- Gutenberg introduced movable-type printing to Europe around 1440; within 50 years, an estimated 15–20 million printed books circulated, shattering the elite monopoly on knowledge. The Gutenberg press
- Columbus reached the Americas in 1492 believing he had found a westward route to Asia; his critics were right that he had underestimated the Earth's size — he never accepted he'd found new continents. European arrival, 1492
- The Columbian Exchange after 1492 moved crops, animals, and diseases between hemispheres; Old World epidemics may have killed up to 90% of the indigenous population of the Americas. The Columbian Exchange
- Martin Luther's 95 Theses (1517) launched the Protestant Reformation; the printing press spread them across Germany in weeks, something impossible a century earlier. The Reformation
- Galileo did not invent the telescope (Dutch opticians did, 1608) but was the first to publish systematic astronomical observations with one, from 1610. Galileo and the telescope
- Isaac Newton's Principia (1687) stated the three laws of motion and universal gravitation, unifying terrestrial and celestial physics — the foundation of science for the next 200 years. Newton's Principia
- The Renaissance was not a sudden 'rebirth' from ignorance; it built directly on medieval scholarship and Islamic-preserved classical texts, with roots reaching back into the 12th century. The Renaissance
Modern (~1800 to present)
- The Industrial Revolution (c. 1760–1840) produced the first sustained rise in per-capita income in human history, ending millennia of near-stagnant living standards. Industrial Revolution
- Darwin's On the Origin of Species (1859) proposed evolution by natural selection; he delayed publishing for ~20 years and released it only when Alfred Russel Wallace reached the same idea independently. Darwin and evolution
- Einstein published four papers in his 1905 'miracle year' — on the photoelectric effect, Brownian motion, special relativity, and mass–energy equivalence (E=mc²). Einstein and relativity
- World War II (1939–1945) was the deadliest conflict in history, with an estimated 70–85 million deaths — the majority civilians, including roughly 6 million Jews murdered in the Holocaust. World War II
- The atomic bombing of Hiroshima on 6 August 1945 killed an estimated 70,000–140,000 people; it was the first use of a nuclear weapon in war, followed by Nagasaki three days later. Hiroshima and Nagasaki
- Apollo 11 landed humans on the Moon on 20 July 1969; the onboard guidance computer had roughly 64 KB of usable memory — vastly less than a modern pocket calculator. Apollo 11 Moon landing
- The transistor, invented at Bell Labs in 1947, is the building block of all modern electronics; today's chips pack tens of billions of transistors onto a single fingernail-sized die. The transistor
- Tim Berners-Lee invented the World Wide Web in 1989–1990 at CERN and released it royalty-free in 1993 — a deliberate choice that let it spread without licensing barriers. The World Wide Web
- The 2017 paper 'Attention Is All You Need' introduced the Transformer architecture that underlies modern large language models, including the system you may be reading this through. The Transformer paper
- ChatGPT reached an estimated 100 million users within two months of its late-2022 launch, one of the fastest consumer-technology adoptions ever recorded. ChatGPT tipping point
Every fact above is mainstream, verifiable history drawn from the site's own event and guide pages. See our methodology and corrections policy.