- The 6th century BC started the first day of 600 BC and ended the last day of 501 BC. This century represents the peak of a period in human history popularly known as Axial Age. This period saw the emergence of five major thought streams springing from five great thinkers in different parts of the world: Buddha and Mahavira in India, Zoroaster in Persia, Pythagoras in Greece and Confucius in China.Pāṇini, in India, composed a grammar for Sanskrit, in this century or slightly later. This is the oldest still known grammar of any language. In Western Asia, the first half of this century was dominated by the Neo-Babylonian or Chaldean empire, which had risen to power late in the previous century after successfully rebelling against Assyrian rule. The Kingdom of Judah came to an end in 586 BC when Babylonian forces under Nebuchadnezzar II captured Jerusalem, and removed most of its population to their own lands. Babylonian rule was ended in the 540s by Cyrus, who founded the Persian Empire in its stead. The Persian Empire continued to expand and grew into the greatest empire the world had known at the time. In Iron Age Europe, the Celtic expansion was in progress. China was in the Spring and Autumn period.
* Mediterranean: Beginning of Greek philosophy, flourishes during the 5th century BC
* The late Hallstatt culture period in Eastern and Central Europe, the late Bronze Age in Northern Europe
* East Asia: the Spring and Autumn period. Confucianism, Legalism and Moism flourish. Laozi founds Taoism
* West Asia: During the Persian empire, Zoroaster, a.k.a. Zarathustra, founded Zoroastrianism, a dualistic philosophy. This was also the time of the Babylonian captivity of the ancient Jews.
* Ancient India: the Buddha and Mahavira found Buddhism and Jainism respectively
* The decline of the Olmec civilization in Central America (en)