Campus Martius

The Campus Martius (Latin for the "Field of Mars", Italian Campo Marzio), was a publicly owned area of ancient Rome about 2 square kilometres (490 acres) in extent. In the Middle Ages, it was the most populous area of Rome. The IV rione of Rome, Campo Marzio, which covers a smaller section of the original area, bears the same name.

According to Rome's foundation myth, prior to the founding of the city, Rhea Silvia, the mother of Romulus and Remus, had her twin sons removed from her possession (by the King of Alba Longa) and were later discarded in the swelling Tiber River, which would later run along the Campus’ western boundary. Washing ashore further downriver, the brothers would return decades later to found a new city. Romulus, who became Rome’s sole king (after killing his brother Remus), ruled for many years until sometime in the seventh century B.C. As he came to the end of his life, a storm cloud descended upon the center of the open field outside the city’s pomerium in order to lift the elderly king to heaven.

This land, “between the city and the Tiber,” became the property of Rome’s last Etruscan king Tarquinius Superbus. After his defeat and exile, the plain was dedicated to the god Mars. Roman men assembled every spring before heading off to fight hostile tribes, surrounding Rome, and citizens gathered for important religious festivals. With the exception of a small altar to Mars near the center of the field, it wasn’t until the fifth century B.C. that any visible changes were made to the field.

In 435 B.C. the Villa Publica was established in a prepared 300m clearing. The area was meant to be a gathering space for citizens to congregate every five years, to be counted in a census. Free from any permanent structures, no additions would be made for another two centuries.

With the advent of the Punic Wars in the mid-third century B.C. Roman military expansion moved out of the Italian peninsula, resulting in the reduction of seasonal musters on the field. The number of foreign wars, however, greatly increased the amount of wealth flowing into Rome. Generals who had sworn to various deities to build temples in their honor if victorious, used the vast amounts of wealth to fund these construction projects. Besides temples and wooden markets, entertainment venues were built also, though they were to be temporary.

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