The Sea and Civilization: A Maritime History of the World

by Paine, Lincoln

  The adoption of the compass for navigation contributed to the development of the medieval portolan, or sea chart, by Mediterranean navigators. The Italian portolano originally referred to a collection of written sailing instructions, the oldest surviving of which is Lo Compasso da Navigare. In time these were accompanied by maps that showed with remarkable felicity the outline of the Mediterranean coast. This attempt at geographic realism was a sharp departure from the highly stylized—and useless for navigation—medieval T-O maps, the intent of which was to represent an ordered world with Jerusalem at the intersection of the T, the arms of which represent the Danube, the Nile, and the Mediterranean. Between the arms lay Europe, Asia, and Africa, and the whole was encircled by Oceanus, the O. In addition to their realism, portolans are characterized by the liberal incorporation of wind roses each with radiating rhumb lines extending to the edges of the map to create a bewildering tangle of intersecting lines. These were colored according to widely adopted convention: black or brown for the winds, green for the half winds, and red for the quarter winds. Ports were identified by name—always written on the landward side perpendicular to the coast—and occasionally by flags or other insignia. On Angelino Dulcert’s map of 1339, for instance, Lanzarotto Malocello’s association with Lanzarote is indicated by the cross of Saint George, tutelary saint of his native Genoa.

  Compasses provide a sense of direction, but not of place. Being able to fix one’s position relative to one’s home port or destination, if the latter was known, was essential. The easiest way to do this was by reference to a stationary object on land, but absent landmarks on the horizon, one must look skyward. The relative constancy with which the moon, stars, and planets make their rounds over the course of the year makes it fairly easy to determine latitude—one’s position north or south of the equator—by measuring the angle between the horizon and either the sun or, in the northern hemisphere, the North Star. The oldest instrument for measuring altitude was the astrolabe, the origins of which can be traced to classical antiquity. The astronomer’s astrolabe was too cumbersome and complex to be useful at sea (Chaucer’s unfinished Treatise on the Astrolabe, the oldest technical manual in English, runs to fifteen thousand words), but the Portuguese had a mariner’s astrolabe by 1481. Use of this simpler instrument was widespread and it is mentioned in the accounts of voyages by Bartolomeu Dias, Vasco da Gama, and Pedro Álvares Cabral. Developed somewhat before the mariners’ astrolabe was the mariner’s quadrant, which appears in the written record around 1460. Other devices added to the navigator’s repertoire included the cross-staff (end of the fifteenth century), Davis’s backstaff (end of the sixteenth century), octant (1730), and, ultimately, the sextant (1759), which remained the standard tool for navigators until the development of electronic navigation. A practical method of determining longitude—one’s position east or west of a given meridian—at sea would have to await the invention of an accurate timepiece in the eighteenth century.

  Of Caravels and Carracks

  Improvements in navigational practice were accompanied by advances in shipbuilding. The medieval period had seen the maturing of two distinct traditions, the shell-first cogs of the Atlantic coast and the Baltic and the frame-first round ships of the Mediterranean, which could reach impressive size. A Genoese contract of 1268 called for the construction of ships measuring thirty-seven by nine meters. The major drawback to sailing such large ships, however, was their unwieldy lateen rig. Although lateen-rigged vessels can sail closer to the wind than square-riggers, which work best with a following wind, they are more difficult to handle. It is impossible to shorten sail in a lateener by furling it on a yard or boom. Instead, the yards must be lowered, the larger sails removed, and smaller ones bent on. Even tacking is a laborious process that requires lowering the yard—which could be fifty meters long—from the mast, swinging the yard and sail to the vertical, and repositioning them on the leeward side of the mast, evolutions that required large crews.

  Soon after Mediterranean shipwrights began building cogs modeled after northern European prototypes they began experimenting with new sail configurations that incorporated both the fore-and-aft lateen of the Mediterranean and the square sail of the north, a change that yielded ships with three and four masts, square sails set forward and lateen sails aft. Columbus’s Santa María set five sails: a single square sail on the foremast, a square mainsail and topsail on the main, a lateen sail on the mizzen, and a square sail set below the bowsprit called a spritsail. As time went on, Mediterranean sailors knew these vessels simply as “ships”—naves in Italian, não in Portuguese, and nao in Spanish—while the English used the word “carrack.”

  At the same time that the nao was emerging as the standard cargo carrier of the day, and also a formidable warship, the narrower, more versatile caravel had evolved from the qarib, a smaller general-purpose vessel associated especially with North Africa and the Iberian Peninsula. The oldest mention of a caravela dates from about the thirteenth century, although there is no clue to its rig or dimensions and the evidence for its subsequent development is sketchy. At the start of the fifteenth century, caravels seem to have been generally two-masted, lateen-rigged vessels (caravela latina), but by midcentury, when they were in widespread use in Portugal and southern Spain, they were also being built with three masts. Rigged with square sails on the fore-and mainmasts and a lateen mizzen, the caravela redonda was more efficient running before the wind, while its comparatively high length-to-beam ratio made it more maneuverable than the nao. Not surprisingly, the heyday of the caravel and nao coincides with the period of Atlantic exploration that began under the auspices of Dom Henrique of Portugal and reached its apogee with Columbus, and they were the forerunners of the square-rigged ships of the classic age of European sail that followed.

  Dom Henrique and His Time

  Dom Henrique—Prince Henry, “the Navigator”—was one of the earliest and most vigorous promoters of the commercial potential of the Atlantic Ocean. The third son of João I and the English Philippa of Lancaster, he is often credited with founding a school of navigation at Sagres in southwest Portugal. In point of fact Henrique was not a mariner—he probably never sailed farther than northern Morocco—and he had no school at Sagres or anywhere else. Henrique was motivated by an abiding belief in the medieval concept of just war, and an obligation to preach the true faith to heathens and crusade against heretics and Muslims. A strong advocate of the Church militant, as a teenager he cajoled his father to embark on a crusade against Morocco, and he took part in the capture of Ceuta in 1415. The victory proved something of a white elephant, for the city was of little economic or strategic significance to Portugal but costly to maintain and impossible to surrender without losing face. A subsequent Portuguese attack on Tangier, thirty miles to the west, failed, and Henrique eventually turned to more commercial pursuits.

  Under his sponsorship, Portuguese caravels reached the archipelagoes of the eastern Atlantic and opened the coast of Guinea, as West Africa was called, which was a source of gold, slaves, and malagueta pepper, a spice of the ginger family used as a substitute for black pepper. His interest in the coast of Africa derived partly from his failed efforts to establish Portuguese control of the Canaries, which Castile had claimed in the early fifteenth century. Ever alert to the possibility of commercial advantage, in the 1420s Henrique sponsored a series of voyages down the coast of Africa in the apparent hope of establishing a kingdom of his own, rich in slaves, gold, and the produce of the untapped coastal fisheries. In the 1430s, he organized the colonization and exploitation of the Madeira Islands for lumber, wine, and, from the 1450s, sugar. (Originally cultivated in New Guinea, sugar had been introduced to the Mediterranean by Muslim traders.) By the end of the century, Madeira was the largest exporter of sugar in the world, shipping more than 1,200 tons per year to Europe. Henrique initiated the settlement of the Azores in 1439, and judging from the rapid rise in their population and industrial and agricultural output, navigation bet
ween Portugal and the two island groups was considerable from the start.

  By 1434, the Portuguese knew the coast of Africa as far as Cape Bojador—the Bulging Cape—south of the Canaries in what is now Western Sahara and until then widely believed to be the southern limit of safe navigation. In that year, Gil Eanes passed the cape. Antão Gonçalves and Nuno Tristão reached Rio de Oro (Dakhla, Western Sahara), the site of a few Moorish villages whose inhabitants were captured and enslaved in 1441, and in that year or the next Tristão reached Cabo Bianco (Nouadhibou, Mauritania). In 1445, an expedition reportedly numbering twenty-six ships sailed for Rio de Oro, and a few vessels continued on to the Senegal River and Cape Verde. Three years later the Portuguese built a trading post near Rio de Oro on the small island of Arguin in the Mauritanian gulf of the same name. Thanks to its supplies of freshwater, this became the center of a lucrative trade in ivory, gold, and slaves, and of a coastal fishery.

  In 1454, when the Venetian merchant Alvise da Cadamosto stopped in Portugal en route to Flanders, Henrique offered him three-quarters of the proceeds of any expedition to Guinea he fitted out himself, or half if he used one of Henrique’s ships. The following year he sailed south. Cadamosto’s account is one of the liveliest of the era to survive, for he has an eye as much for the people and their customs as for their trade. He offers enticing details of the founding and prosperity of the Madeiras, the Canaries, and Arguin, where “Portuguese caravels are coming and going all the year” and where merchants licensed by Henrique traded “cloaks, carpets, and similar articles and above all, corn [grain], for they are always short of food,” for the raw wealth of Guinea—“every year … a thousand slaves” and gold dust. South of the Senegal River he reached the territory of Lord Budomel, a Wolof king who traded a hundred slaves for seven horses and invited Cadamosto to his house about forty kilometers from the coast. “My journey inland was indeed more to see interesting sights and obtain information, than to receive my dues.” After a month as the Budomel’s guest, he sailed farther south, to a place where the North Star was visible “only when the weather was very clear … about a third of a lance above the horizon. We also had sight of six stars low down over the sea, clear, bright, and large.” This was the constellation Crux, or the Southern Cross, a constellation that would come to serve much the same navigational function in the southern hemisphere that Polaris did in the north. Cadamosto was also one of the first people to sight the Cape Verde Islands, which lie about four hundred miles west of Africa and are first mentioned in official documents in 1460. By this, the year of Henrique’s death, the Portuguese had explored about two thousand miles of coastal West Africa, including expeditions up the Senegal, Gambia, and other rivers. Turning the corner into the Gulf of Guinea would take another decade.

  Regardless of the geographical achievements, Henrique’s sponsorship of these voyages was predicated on financial returns, and he set clear objectives for his captains, regulating the distances to be covered and ensuring that details about the navigation and geography of the coast, trade goods, and prices, and local languages were collected systematically. Once south of the zone of Islamic influence and Arabic speakers, acquisition of this information was hampered not only by the difficulty of the navigation, but by the inability to communicate through interpreters. This would remain a problem until the Portuguese rounded Africa and reached the arabophone coast of East Africa in 1498. The challenges of language and the lack of an indigenous tradition of coastal navigation to draw upon help explain why the pace of Portuguese exploration in the last half of the fifteenth century appears so slow, and why their progress once they reached the Indian Ocean was so swift.

  While one result of the Portuguese voyages down the west coast of Africa was the discovery of a route to India, there is no indication that Henrique had any broader program in mind than crusading against heathens and infidels, and his own aggrandizement. At the time, no one considered the possibility of sailing around southern Africa or of finding a shortcut to the Indies, the goal that had animated the Vivaldi brothers 150 years earlier. Government support for further exploration of the African coast died with Henrique, as Afonso V, his nephew, focused on territorial gains in infidel Morocco. These brutal campaigns proved a hard school for Portuguese soldiers, some of whom later took their fight against Muslims to Asia.

  Defining Space

  European expansion ushered in a new era in world history not simply because it catapulted Eurasia’s comparatively backward west-enders from their obscure peninsula onto the world stage, but because the Europeans introduced to the world a variety of cultural and legal novelties that we now take for granted. Two are particularly indelible. One was the evolving symbiosis between rulers and merchants so characteristic of the Italian city-states like Venice, Genoa, and Florence, through whose influence this dynamic spread to Iberia and northern Europe. The other was the notion that political control could be exercised not only over lands across the ocean but over the oceans themselves. While many had used their navies to extend their authority overseas—to seize islands, or to control strategic passages and choke points—no one had ever presumed to divide the sea preemptively and to treat it as a political space analogous to territory on land. The Romans had called the Mediterranean Mare Nostrum, “Our Sea,” but that was simply a statement of fact, and classical jurisprudence regarded the sea as the property of all people, a global commons. By the thirteenth century, both Venice and Genoa were asserting their jurisdiction over the northern Adriatic and Ligurian Seas, respectively, in an effort to ensure that all goods passed through their ports, where taxes and other fees were collected. According to contemporary legal interpretation, they had earned such jurisdiction by custom, specifically by virtue of having held it for a century or more. Others argued that the city-states could receive a “use” of the sea as a gift from the Holy Roman Emperor, and deny others the freedom of navigation.

  All this changed with a series of papal bulls that asserted Portuguese claims to lands not yet ruled by Christian princes. Confirming the advances made under Dom Henrique’s sponsorship, the bull Romanus Pontifex of 1455 stated that Portugal’s Afonso V “justly and lawfully has acquired and possessed … these islands, lands, harbors, and seas” in Guinea, and that no one was allowed to interfere with his or his successors’ efforts to convert the inhabitants to Christianity. The bull applied not only to Ceuta and Guinea, but “to all those provinces, islands, harbors, and seas whatsoever, which hereafter … can be acquired from the hands of infidels or pagans” in the name of Afonso and his heirs. This was hardly the first instance of the Church’s intervention in secular affairs, but Pope Callixtus III was anxious to settle disputes among western leaders in order to free them to crusade against the Ottomans, who had just captured Constantinople.

  A quarter century later, the Treaty of Alcáçovas between Portugal and Castile included two provisions of especially far-reaching significance. Isabella’s right to the throne of Castile was acknowledged, and the dispute over the Canary Islands was resolved in favor of Castile. The Portuguese retained ownership of Madeira, the Azores, and the Cape Verde Islands, and they were given free rein in the exploration of the Atlantic. Moreover, the treaty enjoined Isabella and Ferdinand of Aragon, her husband, to forbid their subjects or anyone “equipped or provisioned in their ports” to sail to the Portuguese islands or the “lands of Guinea discovered or to be discovered.” Alcáçovas thus gave Portugal the lion’s share of the territorial gains, and it was clear that should the Spanish seek out new lands via the Atlantic, they would have to go north or west. As it happened, the Canary Islands, which they retained, proved the ideal point of departure for ships sailing westward to the Americas, as Christopher Columbus and his followers would soon learn.

  With the threat of Castilian interlopers removed, the Portuguese were free again to pursue their Atlantic trade. The possibility that a round-Africa sea route to the Indies might exist began to take hold after the Portuguese turned into the Gulf of Guinea
in 1471. Credit for acting on this possibility goes to Henrique’s grandnephew, João II, who fostered a program of maritime expansion with a view specifically to circumnavigating Africa. He began by sending six hundred soldiers and craftsmen to build a fortress at São Jorge da Mina (Elmina, Ghana), which became the focal point of Portugal’s West African trade in slaves and gold and the base of operations for voyages farther south. The Portuguese crossed the equator around 1473, and in 1482 Diogo Cão reached the mouth of the Zaire (Congo) River, “which enters the sea with such a rush that 20 leagues [sixty miles] from the coast its waters are sweet.” A few years later Cão got as far as Walvis Bay, Namibia. In addition to extending Portuguese knowledge of the physical geography of Africa, these voyages introduced the Portuguese to the kingdom of Congo, which would become among the largest suppliers of African slaves to the Americas, as the Portuguese would be the most important carriers.

  At this point, the possibility that the Portuguese might actually reach the Indian Ocean by sea was so real that João dispatched four expeditions to the east in one year, two by sea, and two overland through the Levant. He had two distinct objects in view: to reach the Christian king of Ethiopia and to ascertain the likelihood of reaching the Indian Ocean by sea and assess the commercial conditions there should that be achieved. The emissary to Ethiopia died, but Pêro da Covilhã spent five years visiting Aden, Cannanore, Calicut, Goa, and the coast of East Africa before returning to Egypt. Learning of his fellow emissary’s death, Covilhã may have sent home an account that stressed the trade of Calicut and mentioned that it was possible to reach there from “the Guinea Sea,” though it is unlikely that any report reached Portugal before the late 1490s. He then went to Ethiopia, where he remained until his death.