Five thousand years on one line
The timeline below places the five eras covered on this site against each other, with a few of the states and empires that shaped them. Each tick marks a century. Select an era name to open its own timeline and study guide.
- Ancient world3000 BCE to 500 CE
- Medieval world500 CE to 1500 CE
- Early modern1450 CE to 1750 CE
- Revolutions1750 CE to 1900 CE
- 20th century1900 CE to 2000 CE
- Old Kingdom Egyptc. 2700 BCE to 2200 BCE
- Indus Valley citiesc. 2600 BCE to 1900 BCE
- Shang dynastyc. 1600 BCE to 1046 BCE
- Achaemenid Persia550 BCE to 330 BCE
- Han dynasty206 BCE to 220 CE
- Roman Empire in the west27 BCE to 476 CE
- Mongol Empire founded1206 CE
- Abbasid Caliphate750 CE to 1258 CE
- Ottoman Empirec. 1299 CE to 1922 CE
- Mughal Empire1526 CE to 1857 CE
- Qing dynasty1644 CE to 1912 CE
On a small screen, swipe the timeline sideways to see all of it.
Skills guides
Read a primary source
Sourcing, context, close reading and corroboration, with a checklist you can use on any document.
Skill 2Handle dates and periods
BCE and CE, how centuries are named, the calendar change, and why historians argue about periods.
Skill 3Understand historiography
How the writing of history has changed, and how to compare two historians who disagree.
Skill 4Write a history essay
Questions, thesis statements, paragraphs built on evidence, and citing sources the way historians do.
Skill 5Prepare for AP and college exams
The historical thinking skills, the main written tasks, and a revision plan that uses them.
Era study guides
The ancient world
Mesopotamia, Egypt, the Indus Valley, China, Persia, Greece and Rome.
500 to 1500The medieval world
Byzantium, the Islamic caliphates, Tang and Song China, the Mongols and medieval Europe.
1450 to 1750Early modern
Print, ocean voyages, the Reformation, gunpowder empires and the Scientific Revolution.
1750 to 1900Age of revolutions
Industry, the Atlantic revolutions, nationalism, abolition and the new empires.
1900 to 2000The 20th century
Two world wars, the Cold War, decolonization and the end of the Soviet Union.
How these guides are written
Every guide sticks to events and dates that historians broadly agree on. Where a date is approximate, it carries "c." for circa. Where scholars disagree about meaning, the guide says so and explains the main positions without picking a winner for you. We don't put words in the mouths of historical figures, and we avoid quotations we can't trace to a reliable edition.
The guides are short on purpose. They give you a frame to hang your reading on, and then point you to the kinds of sources and questions that will take you further. A textbook or a good survey will always hold more detail than any page here.
Ways to use this site
- Before a course: read the era guide and skim its timeline so the lectures have somewhere to land.
- During a course: use the primary source checklist every time you meet a new document.
- Before an exam: work through the exam skills guide and practice one written task a week.
- For your own reading: start with the historiography guide, which explains why two good books on the same subject can disagree.
Questions about studying history
Do I need to memorize lots of dates?
You need enough dates to put events in order and to see what was happening at the same time elsewhere. Most courses care more about causes, consequences and evidence than about exact days. Learn the anchor dates on each era timeline and build out from them.
Are these guides enough to pass an AP exam?
No single website is. Use the guides alongside your course textbook and the official course description from the College Board, which sets out what each exam covers.
Why do some dates have "c." in front of them?
It stands for circa, Latin for "around." Early dates often come from archaeology, king lists or later records, so historians give a best estimate. The dates and periods guide explains this in more detail.