In the nineteenth century, historians began to classify the periods of human prehistory into three ages: Stone, Bronze, and Iron. Of these three, the period known as the Bronze Age (lasting approximately from 3300 to 1200 BCE) was the most significant, not just because people began to work metal on a large scale for the first time but because of other changes taking place. People started to live in large, permanent sites that became the first cities. Agriculture replaced hunting and gathering as the principal means of producing food.

The Sumerians settled in the area known as Mesopotamia, between the Tigris and Euphrates Rivers, around 5,000 years ago. They produced many fundamental changes to the way in which human societies developed - these were the first city-builders, the first people to use wheeled vehicles, the first methodical astronomers, and the first people to develop a sophisticated written language. The Sumerians also produced art, music, and literature as well as created some of the first professional soldiers the world had ever seen.

Rome is a city of myth and legend. The Eternal City, the city of the seven hills, the sacred city, the caput mundi, the center of the world, Roma, Rome, by any of her many names is a city built of history and blood, marble and water, war and conquest. From legendary beginnings, a city rose from the swamp surrounded by the seven hills and split by the Tiber River. Built and rebuilt, a sacred republic and a divine empire, blessed by a thousand gods and by One, the story of her rise and fall has been told and retold for a thousand years and is still relevant in today's world, as echoes of her ancient glory have shaped our culture, laws, lifestyle, and beliefs in subtle and pervasive ways.

An upstart French duke who sets out to conquer the most powerful and unified kingdom in Christendom. An invasion force on a scale not seen since the days of the Romans. One of the bloodiest and most decisive battles ever fought.

At one point, the Japanese Empire was one of the largest the world had ever seen, governing almost 20 percent of the total population of the Earth. One of the most striking features of this empire was the rapidity with which it grew. In 1870, Japan was a largely agrarian nation with a culture and society based on feudal values.