This is my attempt at a cheat-sheet approach to remembering key historical or periods from the Big Bang all the way up to world war 2. I will divide this into several sections :

• History of the Universe
• History of Life
• Pre-Civilisation Human History
• Ancient Civilisations (3500BC-600BC)
• Classical Civilisations (600BC-600AD)
• Medieval Civilisations (600-1500)
• Early Modern Period (1500-1800)
• Modern Period & World Wars I & II (1789-1945)
• Global Civilisation (1945-present)

Online History sources include

• Wikipedia History of the Universe
• PBS Nova History of the Universe
• PBS Deep Space Timeline
• A short History of the Universe

• Wikipedia History of Life
• PBS History of Life
• University of California Paleontology Online
• Wikipedia History of the Earth

• Encyclopedia of World History, Peter Stearns, 2001
• A Short History of the World, HG Wells, 1922

• 13.7 Billion Years ago - Big Bang
  • - 10^-32 second after Big Bang (abb) - hyper-inflation
  • 10^-32 - 10^-6second - inflation slows, gravity emerges followed by strong , weak and electromagnetic forces. Matter consists of fundamental particles including quarks, electrons, photons, and neutrinos.
  • 10^-6 - 1 second abb - hadrons (protons and neutrons) form
  • 3 - 20 minutes abb- deuteron, helium and lithium nuclei form. 3 times as much hydrogen than helium by mass. Only traces of other nuclei.
  • 300,000 years abb - expanding cloud of gas cools enough for electrons to associate with nuclei forming atoms
  • .5 - 1 billion years abb - earliest stars and galaxies form
  • 1 - 3 billion years abb - larger galaxies with black holes and quasars at their centre form
• 7 - 10 billion years ago (bya)- Milky Way galaxy forms
• 4.6 bya - Solar System forms
• 3.7 bya - first life on Earth
• 1.7 bya - multi-cellular life on Earth
• ———————
• 3.3 billion years from now - Milky Way collides with Andromeda
• 6.3 billion years from now - Sun dies
• 100 trillion years from now - Stars have all blown up and collapsed into black holes and neutron stars, or have withered into white dwarfs.
• 10³⁷ years from now - After an epoch of proton decay, the only stellar-like objects remaining are evaporating black holes.
• 10¹⁰⁰ years from now - Black holes have evaporated. Only fundamental particles remain: photons of colossal wavelength, neutrinos, electrons, and positrons.

• Hadean Eon : 4.6 - 3.8 billion years ago (bya)
  • 4.6 bya - Earth forms
  • 4.4 bya - Earth's crust forms
  • 4 bya - Clouds, rain and oceans
• Archean Eon : 3.8 - 2.5 bya
  • 3.8 bya - first life on Earth
  • 3.5 bya - photosynthesis starts
• Proterozoic Eon : 2.5 bya - 550 mya
  • 2.4 bya - oxygen becomes significant component of the atmosphere
  • 1 bya - multicellular plants (algae) and animals
  • 770 - 750 mya - first ice age
• before 550 mya is aka the Precambrian Period or Supereon. After 550 mya is aka the Phanerozoic Eon.
• Paleozoic (Primary) Era : 550 - 250 mya
  • Cambrian - small shelled animals, corals
  • Ordovician - starfish, jawless fish
  • Silurian - land plants, ferns, sharks, fish
  • Devonian - first tetrapods - evolution of fish onto land
  • Carboniferous - reptiles, amphibians, spiders, conifers, amniotic eggs (340 mya), synapsids
  • Permian - synapsids (proto-mammalian reptiles) dominant.
• 250 mya - Extinction event, 83% of species die off
• 300 mya - 250 mya - last supercontinent Pangaea exists
• Mesozoic (Secondary) Era : 250 - 65 mya
  • Triassic - turtles, lizards, dinosaurs, mammals
  • 200 mya - Tr-J extinction event allows dinosaurs to start becoming dominant. Kills > 50 % of species.
  • Jurassic - squids, frogs, birds
  • Cretaceous - dinosaurs dominant, flowering plants, snakes, modern fish, toothed birds
• 65 mya - Meterorite extinction event (off Yucatan peninsula) kills off most large animals
• Cenozoic Era : 65 mya - present
  • Tertiary - mammals dominant, grasses, apes, hominids
  • Quaternary
    • Pleistocene (1.8 mya - 8000 ya) - mammoths, Neanderthals
    • Holocene (8000 ya - now) - modern humans

Human historical ages based on behavioural and cultural characteristics vary significantly based on location since different areas developed at different rates. Figures given here are a rough average estimate.

• 4 mya - earliest humans
• Stone Age : 2.5 mya - ~3000 BC
  • Paleolithic age - 2.5 mya - ~8000BC - Still in the Pleistocene era. Human ancestors roam as bands of hunters/gatherers and use simple stone tools. Evolution from Homo Habilis to Homo Sapiens Sapiens. Ends when the last Ice age (and the Pleistocene era) ends.
  • Mesolithic age - ~8000BC - ~6000BC - Rising sea levels force a need to adapt. More complex settlements and the first tribes appear. Microlithic tools and boats are developed and fishing becomes a source of food.
  • Neolithic age - ~6000BC - ~3000BC - Agriculture (farming and herding) and related tools (plough, hoe, yoke etc) are developed. Domestication of animals begins. The earliest towns and temples are built.
• Bronze Age : ~3300BC - ~1200BC - Bronze (an alloy of copper and tin or of copper with naturally occurring arsenic) comes into use. In some areas this is preceded by a Copper Age.
  • 3000BC - 1450BC - Minoan civilisation on Crete. Beginning of writing.
  • 1650BC - 1200BC - Mycenaean civilisation based around fortified palaces or acropolises. Further development of Minoan civilisation including writing. Homer's epics including the Iliad are set in this period.
• Iron Age : ~1100BC - 800BC - Iron and steel are used for weapons and curring tools. This is the final of the 3 prehistoric ages and ends with the beginning of the historical period. The Greek Dark Ages occur during this period, triggered by invasion of Dorian people with iron weapons. Art, civilization and written language disappear.
• Classical Era : ~800BC - ~500AD - Period comprising the interlocking civilizations of Ancient Greece and Ancient Rome, collectively known as the Greco-Roman world.
  • ~800BC - ~500BC - Greek Archaic period - Marked by significant advancements in political theory and the rise of the polis (city-state) as well as the beginnings of classical philosophy, theatre, poetry and the reintroduction of written language.
  • ~500BC - 323BC - Classical Greek period or golden age. Much of modern politics, artistic thought, scientific thought, literature, and philosophy derives from this ancient society. Wars between city-states led mainly by Athens and Sparta. Ends with the rise of Macedon and the short-lived rise of Alexander the Great (336BC-323BC)
  • 323BC - 330AD - Decline of Greek civilisation and capture by Romans (146BC)
• Middle Ages
• Reformation & Renaissance