NOW PASSING · Begin the journey
Density
Power & exchangeOur World

Empires

Trace the states that connected peoples—and the borders they contested.

Subject guide · scope, chapters & sources ↗
Origin depth
Official Earth time scaleSelect an eon on the road to reveal its eras.ICS 2026/06 ↗
Cosmic Originsbefore Earth’s geological eons
03
c. 4.54 billion years agoSolar System

Earth takes shape

Rock and metal gather around the young Sun.

Specimen / cast
Jon Taylor · CC BY-SA 2.0
04
At least 3.5 billion years agoEarth

Microbial life leaves evidence

Ancient rocks preserve traces of a living planet.

Specimen / cast
Didier Descouens · CC BY-SA 4.0
05
c. 2.4 billion years agoAtmosphere & oceans

Oxygen transforms the atmosphere

Microbial photosynthesis changes the chemistry of Earth.

Specimen / cast
Kjoonlee · CC BY 4.0
06
c. 1.8 billion years agoEarth

Complex cells diversify

Cells with internal structures establish a new branch of life.

Specimen / cast
Fritzmann2002 · CC BY-SA 4.0
08
By c. 200 million years agoEarth

Early mammals live alongside dinosaurs

Small mammals and their close relatives are part of Mesozoic ecosystems.

Specimen / cast
Ghedoghedo · CC BY-SA 3.0
09
c. 56 million years agoAsia, Europe & North America

Early primates diversify

Small tree-dwelling primates spread through warm forests.

Specimen / cast
Ghedoghedo · CC BY-SA 3.0
10
c. 7 million years agoAfrica

The hominin story begins

A lineage of African apes starts following its own evolutionary path.

Object
Oryctes · CC BY-SA 3.0
11
c. 2.8 million years agoAfrica

Early Homo enters the fossil record

A jaw from Ethiopia preserves evidence attributed to our genus.

Specimen / cast
Brian Villmoare · CC BY 4.0
12
c. 300,000 years agoAfrica

Homo sapiens emerge

Our species appears within a diverse human world.

Object
Jonathan Chen · CC BY-SA 4.0
13
c. 60,000–40,000 years agoGlobal

Humans journey beyond Africa

Later waves of migration expand our species’ global presence.

Object
Jonathan Chen · CC BY-SA 4.0
14
c. 10,000 BCEGlobal

The agricultural turn

Communities reshape land, food, and settlement.

Object
Gary Todd · CC0
16
c. 2,350 BCEMiddle East

Akkadian Empire

Sargon unites Mesopotamian city-states.

Object
Gary Todd · CC0
17
c. 320 BCESouth Asia

Mauryan Empire

A dynasty begins a major South Asian unification.

Object
Chrisi1964 · CC BY-SA 4.0

Road complete

You’ve reached the end of Empires

Return to “Writing records the world” and continue along The Human Story, or search for another origin below.