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 - more synapsids (proto-mammalian reptiles).
• 250 mya - Extinction event, 95% of life dies off
• 300 mya - 250 mya - last supercontinent Pangaea exists
• Mesozoic (Secondary) Era : 250 - 65 mya
  • Triassic - turtles, lizards, dinosaurs, mammals
  • Jurassic - squids, frogs, birds
  • Cretaceous - more dinosaurs, 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 - more mammals, grasses, apes, hominids
  • Quaternary
    • Pleistocene (1.8 mya - 8000 ya) - mammoths, Neanderthals
    • Holocene (8000 ya - now) - modern humans