In 510 BC, after a protracted struggle with its Etruscan kings, the nobility of Rome overthrew their monarchy and established a republic. From its very beginning the Roman Republic was a highly unified state, much more so than any of its Greek counterparts, though with its emphasis on foreign conquest it did share some similarities with Sparta. Rome's great rival was Carthage, a Phoenician colony in northern Africa, which controlled most of the trade of the western Mediterranean. It would be another three centuries before Rome absorbed the Greek city-states into its own empire in 146 BC.

The Persian Empire:
Asia & Egypt: Originally founded by Cyrus the Great in 559 BC, the Persian Empire succeeded the Babylonian Empire in becoming the dominant power of the Near East. Drawing on the rich history of 'multi-national' empires that had dominated the region since the third millennium BC, Cyrus sought to make his Achaemenid Empire the greatest of them all - a true 'universal empire'. By the time of Darius an innovative system of local administrators ensured control of a vast area extending as far east as northern India, and as far west as Egypt. However, both Darius and his son Xerxes came unstuck in their efforts to defeat independent Greece and thereafter their heirs were more concerned with keeping their vast empire together than expanding it.

In the far Eastern corner of China the Zhou Dynasty, a feudal-type society based on family dynasties, was coming to the end of a long period of decline. Originating in 1027 BC the Zhou had been an amalgam of city-states that had become progressively centralized and which had thrived until 771 BC when barbarians, allied to rebel lords, sacked their capital and court. In 551 BC, the famous Chinese Scholar Confucius was born. Probably writing around the same time as Cleisthenes brought democracy to Athens, Confucius died in 479 BC, a year before the Battle of Salamis. Thereafter China began a long period of civil war that would last for over 250 years.

During the 5th and 6th centuries BC, the ancient Olmec civilization was coming to an end in Mexico. At the about same time, the Mayan civilization was rapidly expanding in Honduras, Guatemala and El Salvador. In time the Mayans would become the most advanced civilization of the Americas; developing huge monumental architecture, hieroglyphic writing, and a solar calendar more accurate than was used in Europe until the 16th century.