Timeline: 500-1 BC
Venus de Milo (Louvre Museum)
All over the world, this was a time of unification, both by trading with each other and by building empires. In China, first the Chin Dynasty and then the Han Dynasty united China and built strong trade networks both inside China and abroad, trading with India, South-East Asia, and across Central Asia to the Persian Empire along the Silk Road. In Central Asia, someone invented camel saddles about 200 BC, which made the trading easier.
Across the Pacific Ocean in Central America, the Maya and the Zapotec were also building strong empires, running from Mexico down to Venezuela. Further north, the Hopewell culture united people from Louisiana all the way north to Ohio and Wisconsin, trading in canoes up and down the Mississippi and other rivers.
Across the Atlantic, in Africa, some Bantu people from West Africa began to spread out across Africa, bringing their language and their iron tools with them. North of the Sahara, the Carthaginians built another empire all along the coast of North Africa and Sicily. In East Africa, Meroe got more and more involved in trade with West Asia and India.
Still further north, in Europe, Athenian Empire united Greece, only to be conquered in turn by Alexander the Great, who took over the Persian Empire to unite Greece, Egypt and West Asia. Under Greek rule, Eratosthenes discovered that the earth was a sphere, and how big it was, and people argued about whether the earth went around the sun. At the same time, the Romans conquered first the Etruscans, then the Carthaginians in North Africa and the Greeks, then Gaul (France), and finally united the whole Mediterranean Sea with the conquest of Cleopatra's Egypt.
Finally, in India the great general Chandragupta also formed the Mauryan empire beginning in the 300s BC, and it got even bigger under Chandragupta's grandson Ashoka. All over the world, this was a time of growth and connections among people.