Anatomically modern humans spread out of Africa as hunter-gatherers in around 70,000 BP (see map) eventually between bout 10,000 and 3000 BCE mostly coalescing into settled farming communities with their own suites of domesticated animals and plants.
New urban settlements spread outwards from the six regional centres with trade at first beirg local and concentrated along the fertile river valleys where most settlements had become established. Trade would later expand between coastal areas. In Asia this was most evident in the seas around China and Japan, and the coasts of India In the West the river valley communities of Egypt and Mesopotamia increased their trade across the Mediterranean this being a feature of the Mycenaean and especially Phoenician civilizations the Greek and Roman Emipres supported trade with sophisticated imperial administrations based on written records Trade routes were like life-giving arteries and between 120 BCE-1450 CE the Silk Road (a network of overland communication routes between the West and East across the steppes of Central Asia) passed mostly luxury goods between the two hemispheres thriving especially during the period of the Rman Empire in the West and the Han Dynasty in the East.
The benefits of commerce as a way of enhancing the material conditions of life became clearly evident when from the 15th century, in an Age of Discovery, western culture which was established around the Mediterranean, but mainly in the east, broke out of the Mediterranean to cross the Atlantic. This opened new possibilities for settlement and access to lucrative resources that transferred political and economic power to the coastal cities of northwest Europe. European science, technology, commerce, and general scholarship resulted in the Great Divergence, the increase of European global political and economic power during a period of colonial expansion at the same time as Enlightenment voyages of scientific exploration.
In the West there have been two Dark Ages, the first was the Late Bronze- to early Iron Age Collapse of the Fgyptian and Mesopotamian worlds that lasted about 100 years from 1200 to 1100 BCE in which there was rapid and largely unaccounted decline in Mycenae, the Hittites, Anatolia, Syria, and Egypt during which trade and written language virtually ceased. Wandering semitic tribes of Egypt moved to the Levant, setting up their own kingdom, and it was these people, known as Phoenicians, that revived the lost language, created a 22 letter alphabet using paper and revived trade around the Mediterranean. The second Dark Age occurred in Europe after the collapse of the Roman Empire around 400 CE when literacy and trade was again curtailed with religion and learning confined to monasteries with a small Romanic Renaissance about 900 CE followed by an Arabic revival of learning before the Italian Renaissance of classical learning of the 13-14th centuries.
In the 16th and 17th centuries increasing social integration and complexity enabled Western Europe to overcome the barrier of the Atlantic Ocean to establish a trading highway with the New world. By the 19th century Britain had seized the lion’s share of this resource exchange making it the world’s first global power and establishing a truly global economy. As, through the 20th century, the Indian and Pacific Oceans opened up further to the Western influence, by the 21st century the United States had deposed the United Kingdom and it was the Pacific that was becoming the world focus, accelerating East Asian development and enabling China to challenge America for global political and economic dominance.
Viewed from a Western imperialist perspective we see a transition from small agricultural village societies highland Mesopotamia that moved into the fertile rver valleys of the Tigris and Euphrates which offered the benefits of river trade. From here large-scale agriculture was subsequently adopted in the river valleys of the Nile in Egypt and Indus in India. But as cities and trade grew the scale of activity expanded and the focus of civilization moved westward following maritime trade within the Mediterranean Sea which provided resources on a scale necessary for yet more social development and complexity that would see the rise of the Mediterranean Phoenician trade network and eventually the ascendancy of the Greek and Roman Empires. When the Atlantic Ocean was conquered giving access to the resources of the New World it was cites on the Atlantic seaboard of western Europe that would now thrive, those of Spain, Portugal, Holland, France, and England. These countries would, in turn, forge global empires through sea power that broke out of the introspective classical world of the Mediterranean to claim the Atlantic, Indian, and Pacific Oceans.