The 2nd millennium BC marks the transition from the Middle to the Late Bronze Age.
Its first half is dominated by the Middle Kingdom of Egypt and Babylonia. The alphabet develops. Indo-Iranian migration onto the Iranian plateau and onto the Indian subcontinent propagates the use of the chariot. Chariot warfare and population movements lead to violent changes at the center of the millennium, and a new order emerges with Greek dominance of the Aegean and the rise of the Hittite Empire. The end of the millennium sees the transition to the Iron Age. World population begins to rise steadily, reaching some 50 million towards 1000 BC.
Spending much of their energies in trying to recuperate from the anarchic situation that was at the turn of the millennium, the most powerful civilizations of the time, Egypt and Mesopotamia, turned their attention to more modest goals. The Pharaohs of the Middle Kingdom of Egypt and their contemporary Kings of Babylon, of Amorite origin, brought good governance without much tyranny, and favoured elegant art and architecture. Farther east, the Indus Valley civilization was in a period of decline, possibly as a result of intense, ruinous flooding.
The 2nd millennium was the thousand-year period that commenced on January 1, 1001 and ended on December 31, 2000, encompasses the High Middle Ages, the Renaissance, the Early Modern Age, the age of Colonialism, industrialization, the rise of nation states, and culminates in the 20th century with the impact of science, widespread education, and universal health care and vaccinations in many nations. The centuries of expanding large-scale warfare with high-tech weaponry (of the World Wars and nuclear bombs) are offset by growing peace movements from the United Nations, the Peace Corps, religious campaigns warning against violence, plus doctors and health workers crossing borders to treat injuries and disease and the return of the Olympics as contest without combat.
Scientists prevail in explaining intellectual freedom; humans take their first steps on the Moon during the 20th century; and new technology is developed by governments, industry, and academia across the world, with education shared by many international conferences and journals. The development of movable type, radio, television, and the internet spread information worldwide, within minutes, in audio, video, and print-image format to educate, entertain, and alert billions of people by the end of the 20th century.