History Atlas
What History Atlas is, and what is and is not being claimed. For the editorial method behind the entries, see How This Atlas Works.
What Is History Atlas?
ERAS lead: seven standard periods, their boundaries honestly debated, then civilizations, polities, events and the people who shaped them. The record is of what happened and how we know it, not a verdict on what it meant. Every entry links to what it touches, so browsing tends to lead somewhere useful rather than dead-ending.
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No. Every entry, search and comparison tool is free to read with no account and no paywall. An account adds the things that are yours: starred entries, collections, following a topic, taking part in the forum and in quizzes, and raising a dispute under your own name.
How Are Facts Sourced and Checked?
Every structured fact carries a citation and a status of established, disputed, unknown or held differently, and every source carries a reliability tier. See How This Atlas Works for what the tiers mean.
Is Anything Here Professional Advice?
No. Nothing on this site is medical, legal, financial or other professional advice, and none of it should be used as a substitute for it. It is a reference work about its subject, not a service for making decisions about your own situation. Consult a qualified professional for that.
How Do I Report an Error?
Use the challenges panel on the entry itself, or the contact page if you would rather write than post. Corrections are welcome and are how the atlas gets better.
Why did Aline Barnsdall fire Frank Lloyd Wright from the Hollyhock House project?
Budget and design disputes, though the two stayed on friendly terms afterward.
Cost overruns and repeated disputes over budget and design details led her to terminate him by October 1920, though the two remained on cordial terms afterward; surviving correspondence shows continued warmth even as Wright wrote that she would drop suggestions as a warplane drops bombs and sails away into the blue.Why is Herbert F. Johnson Jr. remembered for a leaky roof and a joke about a chair?
A leak dripped on him at his own Wright house, and Wright's reply became legendary.
The glass-tube skylights of the Johnson Wax Administration Building leaked for years. At a dinner party in Johnson's own Wright-designed home, Wingspread, a leak poured directly onto his head; he telephoned Wright in Phoenix to complain, and Wright's reply, loud enough for the table to hear, was: well, Hib, why don't you move your chair. It became one of the most repeated anecdotes about the two men's relationship.Why did Edith Farnsworth sue Ludwig Mies van der Rohe?
She countersued over cost overruns after he sued her for unpaid fees; the court ruled for him.
Mies sued her first, for unpaid fees, after cost overruns with no written contract between them; she countersued alleging fraud and deceit, claiming he had led her into paying tens of thousands of dollars more than the roughly forty thousand they had originally discussed. The court ultimately ruled for Mies and dismissed her countersuit, though she paid less than his side had sought. How the episode should be read is itself disputed: see the dissent on her page.Did Samuel Bronfman choose Ludwig Mies van der Rohe himself for the Seagram Building?
No, his daughter Phyllis Lambert rejected the first design and led the search that chose Mies.
No. Bronfman initially approved a different architectural firm; it was his daughter Phyllis Lambert who, in a forceful letter from Paris in the summer of 1954, objected to that design and then led the roughly six-week search that resulted in selecting Mies van der Rohe, going on to serve as the project's Director of Planning through its 1958 completion.Did Solomon Guggenheim ever see the museum that bears his name?
No, he died a decade before the museum opened, and Wright died six months before that too.
No. He commissioned Frank Lloyd Wright around 1943 but died on November 3, 1949, roughly a decade before construction finished; the museum opened on October 21, 1959, six months after Wright himself had also died, so neither founder nor architect lived to see it completed.When did prehistory end?
It does not end on one date; it ends wherever and whenever a society first leaves written records.
There is no single date. Prehistory is conventionally said to end wherever a society first produces texts that survive, so the boundary falls at very different calendar dates in different regions: around 3200 BCE with the earliest Sumerian cuneiform in Mesopotamia, around 3100 BCE in Egypt, and as late as around 1200 BCE in China. Prehistory closes region by region, not everywhere at once.What ended the Bronze Age world of the ancient Near East?
The Bronze Age Collapse, a decades-long wave of crises around 1200 to 1150 BCE whose causes are still debated.
The Bronze Age Collapse, a wave of destructions, migrations and state failures that unfolded over decades, roughly 1200 to 1150 BCE, rather than in a single year. Historians and archaeologists still actively debate its causes, including drought, invasion by the so called Sea Peoples, internal revolt, and the breakdown of long distance trade networks; no single explanation is settled.Why do historians disagree on when Classical Antiquity ended?
476 CE is the traditional marker, but many historians see a gradual transformation and prefer 330 or 500 CE instead.
The traditional marker, 476 CE, is the deposition of the last Western Roman emperor, Romulus Augustulus, a convenient political event. Many historians now treat the end of antiquity as a gradual transformation rather than a single collapse, and prefer 330 CE, the founding of Constantinople, or 500 CE as alternative boundaries, since Roman institutions, culture and the Eastern Roman Empire itself continued well past 476 in different forms.When does the medieval period end and the early modern period begin?
Conventionally 1453 (the fall of Constantinople), though 1492 and 1500 are also commonly used markers.
This atlas uses 1453, the Ottoman conquest of Constantinople, as the boundary, but it is one of several commonly used markers. Some historians prefer 1492, Columbus's first Atlantic voyage, or 1500 as a round number, and the transition itself was gradual and regional rather than a single dated event anywhere.Why do the eras on this atlas have different start and end years in different books?
Era boundaries are historians' conventions, not natural facts, so different sources round to different marker events.
Every boundary between two eras on this atlas is a convention chosen by historians for convenience, not a fact discovered in the ground. Real change is almost always gradual: political structures, technologies and everyday life shift over decades or centuries, not in a single year. Sources therefore pick a specific, memorable marker event, a battle, a conquest, a change of ruler, to stand in for a much longer transition, and different scholarly traditions sometimes prefer different markers for the same underlying shift. This atlas records the most common convention as the primary fact and marks its Status as debated wherever real disagreement exists, with the alternative dates and the reasoning behind them recorded in the fact's own note.Why does prehistory end at different times in different parts of the world?
Prehistory conventionally ends where writing begins, and writing was invented independently, at different times, in different places.
This atlas marks the end of prehistory conventionally at around 3200 BCE, when the earliest Sumerian cuneiform writing appears in Mesopotamia. But writing was not invented once and then spread everywhere at the same pace; it was invented independently more than once, in Egypt around 3100 BCE, in China around 1200 BCE, and later still, separately, in Mesoamerica. A region's own prehistory, on the writing based convention, ends only when written records begin there specifically, which is why the same global era can have a different local end date depending on where you are. Some historians go further and challenge the entire writing based convention as biased toward literate, state organized societies; that critique is recorded as a formal dissent on prehistory's own end date fact.When did the medieval period really end?
This atlas uses 1453, the Ottoman conquest of Constantinople, but 1492 and 1500 are both widely used alternatives.
There is no single agreed date. This atlas uses 1453, the Ottoman conquest of Constantinople, as the conventional endpoint of the post-classical, or medieval, period, mainly because it gives a clean, well known hinge between the medieval and early modern eras. Many historians instead prefer 1492, Christopher Columbus's first Atlantic crossing, because it more directly marks the beginning of sustained European contact with the Americas, a change with far larger long-term consequences than the fall of a single city. Still others simply use 1500 as a round marker and treat the actual transition, which involved gradual shifts in trade, technology, religion and political organization across a century or more, as having no single defensible date at all.Is the contemporary period still going, or does it have an end date?
It has no end date on this atlas; it is the still-ongoing era, conventionally started in 1945.
The contemporary period is the one era on this atlas with no end-year fact, and that is deliberate rather than a gap: by definition it is the era still underway. This atlas starts it conventionally in 1945, at the end of the Second World War, though some historians instead prefer 1989 or 1991, the end of the Cold War, treating 1945 to 1991 as its own transitional late twentieth century era. Whichever start date a given source prefers, none of them supplies an end date, because the contemporary period, again by definition, has not ended yet.