Measuring and Mapping Space: Geographic Knowledge in Greco-Roman Antiquity

The following text appears on banner no. 1 in the exhibition space.

We may learn from both the evidence of our senses and from experiences, that the inhabited world is an island; for wherever it has been possible for men to reach the limits of the earth, sea has been found, and this sea we call “Oceanus.” And wherever we have not been able to learn by the evidence of sense, there reason points the way.
Strabo, Geography I.I.8

Measuring and Mapping Space: Geographic Knowledge in Greco-Roman Antiquity explores the ways in which Greek and Roman societies perceived and represented both the known and the unknown worlds, introducing three defining moments in the history of ancient cartography: the ancient era, when notions of geographic knowledge were first formulated and disseminated; the rediscovery of ancient geography through Renaissance sources; and the use of modern technology in recovering and understanding these earlier periods.

What we know about Greek and Roman mapping comes primarily from written sources. As Strabo’s quote above indicates, the ancients used both evidence and their imaginations to envision their world. They understood it to be a sphere (as we do in the modern age), and realized that the three connected continents that they knew (Asia, Europe, and Africa) covered only a small part of its surface. Most geographers believed that these continents were entirely surrounded by seas, and some speculated that there were other “unknown” lands inhabited by societies similar to theirs. Scholars today assume that there were visual representations of these beliefs, but none survive except in Medieval and Renaissance versions, such as the extraordinary world map on view in this exhibition found in a fifteenth- century manuscript copy of the ancient geographer Ptolemy’s Geographia.

By Roman times land surveying and mapping of settlements were well-developed fields, practiced by professional specialists who were supported by a technical literature. However, scholars still debate how common were maps in the modern sense of the term—two-dimensional objective and scaled representations of an area with its main topographic features represented. For practical purposes, Greeks and Romans usually employed what are known as periploi (‘coastal navigations’), which listed ports and landmarks to facilitate commercial and military sailing, and itineraria (‘journeys’), lists of locations and distances based on land routes. Reflecting both of these traditions, the Peutinger Map, displayed in our galleries in a magnificent digital replica, combines elements from earlier maps and road networks by showing the whole extent of the known world as if radiating from the center of Rome.

Spatial representations, particularly those of the globe, became politically charged under the Roman Empire. Starting with Augustus (r. 27 BCE –14 CE ), emperors promulgated their omnipotence through the symbol of the world sphere, a subject that is fully explored in the galleries. During the Early Medieval period, the Church built upon this tradition by incorporating geography in religious treatises as a way to emphasize divine presence in all aspects of human existence, clearly illustrated by the famous manuscript In Apocalypsin of Beatus of Liebana, a rare Medieval copy of which is found in our galleries.

The Renaissance rediscovery of ancient geographic theories and practices enables scholars to reconstruct more precisely the conceptual framework of ancient mapping. Indeed, our understanding of the measuring and mapping of space in Greco-Roman society is mediated through the Renaissance revitalization, reinterpretation, and re- elaboration of these subjects, several examples of which are on display here.

In the modern era scholars have continued to investigate and interpret the geographic legacy of the Greeks and Romans. They have increasingly employed spatial analysis and computing to illuminate aspects of ancient life that go beyond worldview, cartography, and the visual rhetoric of power. The computers in the first gallery provide additional information about the objects on display. They also enable visitors to interact with some of the online tools being developed here at ISAW and at other institutions in pursuit of a full spatial appreciation of the past.