Early world maps
The earliest known world maps date to classical antiquity, the oldest examples of the 6th to 5th centuries BCE still based on the flat Earth paradigm. World maps assuming a spherical Earth first appear in the Hellenistic period. The developments of Greek geography during this time, notably by Eratosthenes and Posidonius culminated in the Roman era, with Ptolemy's world map, which would remain authoritative throughout the Middle Ages. Since Ptolemy, knowledge of the approximate size of the Earth allowed cartographers to estimate the extent of their geographical knowledge, and to indicate parts of the planet known to exist but not yet explored as terra incognita.
With the Age of Discovery, during the 15th to 18th centuries, world maps became increasingly accurate; exploration of Antarctica, Australia, and the interior of Africa by western mapmakers was left to the 19th and early 20th century.
Antiquity
Bronze Age Saint-Bélec slab
The Saint-Bélec slab discovered in 1900 by Paul du Châtellier, in Finistère, France, is dated to between 1900 BCE and 1640 BCE. A recent analysis, published in the Bulletin of the French Prehistoric Society, has shown that the slab is a three-dimensional representation of the River Odet valley in Finistère, France. This would make the Saint-Bélec slab the oldest known map of a territory in the world. According to the authors, the map probably was not used for navigation, but rather to show the political power and territorial extent of a local ruler's domain of the early Bronze Age.Babylonian (c. 6th c. BCE)
Anaximander (c. 610–546 BCE)
is credited with having created one of the first maps of the world, which was circular in form and showed the known lands of the world grouped around the Aegean Sea at the center. This was all surrounded by the ocean.Hecataeus of Miletus (c. 550–476 BCE)
is credited with a work entitled Hecataeus of Miletus#Periodos Ges, in two books each organized in the manner of a periplus, a point-to-point coastal survey. One, on Europe, is essentially a periplus of the Mediterranean, describing each region in turn, reaching as far north as Scythia. The other book, on Asia, is arranged similarly to the Periplus of the Erythraean Sea of which a version of the 1st century CE survives. Hecataeus described the countries and inhabitants of the known world, the account of Egypt being particularly comprehensive; the descriptive matter was accompanied by a map, based upon Anaximander's map of the Earth, which he corrected and enlarged. The work only survives in some 374 fragments, by far the majority being quoted in the geographical lexicon the Ethnica, compiled by Stephanus of Byzantium.Eratosthenes (276–194 BCE)
drew an improved world map, incorporating information from the campaigns of Alexander the Great and his successors. Asia became wider, reflecting the new understanding of the actual size of the continent. Eratosthenes was also the first geographer to incorporate parallels and meridians within his cartographic depictions, attesting to his understanding of the spherical nature of the Earth.Posidonius (c. 135–51 BCE)
of Apameia was a Greek Stoic philosopher who traveled throughout the Roman world and beyond and was a celebrated polymath throughout the Greco-Roman world, like Aristotle and Eratosthenes. His work "about the ocean and the adjacent areas" was a general geographical discussion, showing how all the forces had an effect on each other and applied also to human life. He measured the Earth's circumference by reference to the position of the star Canopus. His measure of 240,000 stadia translates to, close to the actual circumference of. He was informed in his approach by Eratosthenes, who a century earlier used the elevation of the Sun at different latitudes and arrived at a result of roughly 250,000 stadia. Both men's figures for the Earth's circumference were uncannily accurate, aided in each case by mutually compensating errors in measurement. However, the version of Posidonius' calculation popularised by Strabo was revised by correcting the distance between Rhodes and Alexandria to 3,750 stadia, resulting in a circumference of 180,000 stadia, or. Ptolemy discussed and favored this revised figure of Posidonius over Eratosthenes in his Geographia, and during the Middle Ages scholars divided into two camps regarding the circumference of the Earth, one side identifying with Eratosthenes' 250,000 stadion measure and the other with Posidonius' 180,000, which is now known to be about 33% too low. This was the number used by Christopher Columbus to underestimate the distance to India as 70,000 stades.Strabo (c. 64 BCE – 24 CE)
Strabo is mostly famous for his 17-volume work Geographica, which presented a descriptive history of people and places from different regions of the world known to his era. The Geographica first appeared in Western Europe in Rome as a Latin translation issued around 1469. Although Strabo referenced the antique Greek astronomers Eratosthenes and Hipparchus and acknowledged their astronomical and mathematical efforts towards geography, he claimed that a descriptive approach was more practical. Geographica provides a valuable source of information on the ancient world, especially when this information is corroborated by other sources. Within the books of Geographica is a map of Europe. Whole world maps according to Strabo are reconstructions from his written text.Pomponius Mela (c. 43 CE)
Pomponius is unique among ancient geographers in that, after dividing the Earth into five zones, of which two only were habitable, he asserts the existence of antichthones, people inhabiting the southern temperate zone inaccessible to the folk of the northern temperate regions due to the unbearable heat of the intervening torrid belt. On the divisions and boundaries of Europe, Asia and Africa, he repeats Eratosthenes; like all classical geographers from Alexander the Great he regards the Caspian Sea as an inlet of the Northern Ocean, corresponding to the Persian and Arabian gulfs on the south.Marinus of Tyre (c. 120 CE)
Marinus of Tyre's world maps were the first in the Roman Empire to show China. Around 120 CE, Marinus wrote that the habitable world was bounded on the west by the Fortunate Islands. The text of his geographical treatise however is lost. He also invented the equirectangular projection, which is still used in map creation today. A few of Marinus' opinions are reported by Ptolemy. Marinus was of the opinion that the Oceanus was separated into an eastern and a western part by the continents. He thought that the inhabited world stretched in latitude from Thule to Agisymba and in longitude from the Isles of the Blessed to Shera. Marinus also coined the term Antarctic, referring to the opposite of the Arctic Circle. His chief legacy is that he first assigned to each place a proper latitude and longitude; he used a "Meridian of the Isles of the Blessed " as the zero meridian.Ptolemy (c. 150)
Surviving texts of Ptolemy's Geography, first composed, note that he continued the use of Marinus's equirectangular projection for its regional maps while finding it inappropriate for maps of the entire known world. Instead, in Book VII of his work, he outlines three separate projections of increasing difficulty and fidelity. Ptolemy followed Marinus in underestimating the circumference of the world; combined with accurate absolute distances, this led him to also overestimate the length of the Mediterranean Sea in terms of degrees. His prime meridian at the Fortunate Isles was therefore around 10 actual degrees further west of Alexandria than intended, a mistake that was corrected by Al-Khwārizmī following the translation of Syriac editions of Ptolemy into Arabic in the 9th century. The oldest surviving manuscripts of the work date to Maximus Planudes's restoration of the text a little before 1300 at Chora Monastery in Constantinople ; surviving manuscripts from this era seem to preserve separate recensions of the text which diverged as early as the 2nd or 4th century. A passage in some of the recensions credits an Agathodaemon with drafting a world map, but no maps seem to have survived to be used by Planude's monks. Instead, he commissioned new world maps calculated from Ptolemy's thousands of coordinates and drafted according to the text's 1st and 2nd projections, along with the equirectangular regional maps. A copy was translated into Latin by Jacobus Angelus at Florence around 1406 and soon supplemented with maps on the 1st projection. Maps using the 2nd projection were not made in Western Europe until Nicolaus Germanus's 1466 edition. Ptolemy's 3rd projection does not seem to have been used at all before new discoveries expanded the known world beyond the point where it provided a useful format.Cicero's Dream of Scipio described the Earth as a globe of insignificant size in comparison to the remainder of the cosmos. Many medieval manuscripts of Macrobius' Commentary on the Dream of Scipio include maps of the Earth, including the antipodes, zonal maps showing the Ptolemaic climates derived from the concept of a spherical Earth and a diagram showing the Earth at the center of the hierarchically ordered planetary spheres.