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Sea and River Transport

Sea and River Transport


Access to the Sea . In the area of water transport, the medieval Islamic world presents a double face. The Mediterranean Sea and the Indian Ocean formed water frontiers to which Muslims reacted quite differently. The empire conquered by the Arabs between 632 and 711 incorporated an enormous extent of coastline: the Mediterranean coast of Iberia (Spain), the Atlantic coast of Morocco, the southern and eastern coasts of the Mediterranean Sea, all the east and half of the west coast of the Red Sea, the southern coast of the Caspian Sea, and the entire Indian Ocean coast from Yemen to the mouth of the Indus including the Persian Gulf. No empire had comparable access to the sea until the Portuguese and Spanish explorations of the fifteenth century. These coastlines do not all have the same importance, however, in political and economic calculations. Geographically speaking, most of the Muslims’ coastal lands were of restricted value, at least from a transport perspective.

Limits to Navigation . The arid zone that proved so favorable to the pastoralism of its conquerors dictated that there were few navigable rivers and hence few port cities at river mouths. The Nile and the Shatt al-Arab (the river at the head of the Persian Gulf formed by the confluence of the Tigris and Euphrates), provided the only significant river access to the lands behind the coast; but the shifting delta of the Nile prevented the development of a large port city like Basrah in Iraq. In other places steep mountains shadowing narrow coastal plains produced seasonal torrents rather than perennial rivers, as was the case in the Algerian, Lebanese, and Caspian coastlands. Small ports provided stopovers for coastal traders, but they did not connect to major inland trade routes. In still other places, lack of fresh water put a strict limit on human settlement, as on both sides of the Red Sea and Persian Gulf and along the southern coast of Iran and Sind (the lower Indus valley). Only in southern Arabia, from Mocha in Yemen to Musqat in Oman, did occasional small seaports connect with rich hinterlands, but even there geography was destiny, inasmuch as the great sand sea of the Rub’al-Khali (the Empty Quarter) cut off most of southern Arabia from the lands to the north.

Trade Winds . Since sailing ships were the primary means of water transport, the prevailing winds must also be taken into account. Winter storms over the Mediterranean dictated a more or less complete cessation of sea travel for several months of the year. In the Red Sea, the only point of potential maritime contact between the worlds of the Mediterranean and the Indian Ocean, northerly winds prevailed above the latitude of Makkah, making it comparatively inconvenient to sail northward. In the Indian Ocean, seasonal winds—from west to east in summer and from east to west in winter—strongly influenced trading calendars and itineraries. The wind-determined difficulty in navigating the northern portion of the Red Sea manifested itself in technological discontinuity. Mediterranean ships were built and rigged differently from those in the Indian Ocean and Persian Gulf.

Shipbuilding . Roman ship-building practice favored joining the planks on the ship’s hull with mortise-and-tenon joints—that is, put tab A in slot B—held in place by wooden pegs. Ribs were then attached to the inside of the hull for strengthening. This technique changed in the medieval period to that of laying down a keel, attaching a framework of ribs, and nailing the hull planks to the ribs.

In both periods, the finished ship was rigged with a square sail and fitted with oars and oarlocks if military operations were anticipated. In the Indian Ocean and Persian Gulf, shipbuilders bored holes in the hull planks, tied them together with palm-fiber cords, and caulked the seams with bitumen, which was plentifully available from the tar seeps that signaled the immense underground oil reserves of the Gulf. For rigging, Indian Ocean shipmasters used a lateen sail. This large, irregular, four-sided sail presented such a narrow edge to the wind that it is often described as triangular. Compared to the Mediterranean square sail, the lateen design permitted ships to sail more directly into the wind and probably made them more stable since the force of the wind was greater on the wide lower portion of the sail than on its pointed peak. A reason for this difference that was more important than technical advantage or disadvantage, however, was the fact that shipwrights and shipmasters from the southern seas seem to have had little contact with those in the Mediterranean world.

Maritime Zones . The differences between the two zones carried over into politics and trade. Despite the principle legendarily ascribed to the early khalifahs that Muslim lands should never be separated by water, Muslim sea raiders did hold—for varying lengths of time—the Belearic Islands, Malta, Sicily, and Crete. And of course the army that conquered Spain had to be ferried across the strait of Gibraltar. Nevertheless, the idea of linking these maritime holdings commercially or politically, after the manner of the ancient Athenians and Carthaginians or the late medieval Venetians, seems never to have been considered. Naval conquests seem to have been less the product of a centralized strategy of Islamic expansion than of the decay of power in the khilafal center and the corresponding rise of independent local states. Sicily, for example, was conquered from, and remained tied to, the quasi-independent government of Tunisia, and the Balearic Islands were an outpost of the totally independent Muslim state in Spain.

Sea Trade . With respect to trade, the maritime route from Spain to Tunisia and Egypt was the most active. Commercial relations with Christian Europe were few in the early Islamic centuries, with most cargoes being shipped by Jewish traders, who were marginally more welcome in Christian lands, where there were communities of co-religionists, than were Muslim traders. The historian Henri Pirenne’s well-known dictum that the Muslim conquests permanently severed maritime ties between the northern and southern sides of the Mediterranean has been disproved by archaeological and textual evidence. Southern products did continue to reach Europe in early medieval times, but trade unquestionably declined. Christian and Muslim sea raiders made routes that approached enemy territory too closely unsafe.

Maritime Powers . Not until the conquest of Anatolia in the second wave of Muslim expansion did sea power again become a major concern. Turkish Muslim principalities established along the shores of the Aegean Sea in western Anatolia inherited the seafaring expertise and enterprise of their mostly Greek-speaking populations. At the same time, however, the eleventh-twelfth century revival of urban prosperity in Italy stimulated the Venetians, Genoese, and Pisans to establish themselves as a trading presence on the southern and eastern shores of the Mediterranean from Tunisia to Egypt and Syria, with special emphasis on the Crusader States established after 1097. Trade and warfare eventually culminated in a long struggle between the Ottoman Empire and Venice for Mediterranean domination, a struggle that extended well beyond 1500. Based in shoreline fortresses or castle-protected seaports increasingly equipped with large cannon after 1400, oared galleys rowed out to prey on passing enemy shipping. Yet, even then the Muslim states never developed a clear-cut naval strategy based on their control of the southern Mediterranean shoreline from the strait of Gibraltar to Greece, an expanse of territory that had been completely absorbed into the Ottoman empire by 1520.

Political Disunity . Given the extent of the Muslim lands, and their substantial political disunity between 800 and 1500, it is pointless to search for a deep ideological meaning behind the lack of dedication to seaborne trade and maritime political power. It is easier, perhaps, to explain the relative success of the Christian states in this area by looking at the limited possibilities Venice, Pisa, and Genoa had for expansion by land and the consequent push to the sea as the outlet for their ambitions.

Indian Ocean Trade . In the southern seas, Muslim aggression was even less in evidence, despite the isolated undertaking to send part of an invasion force from Basrah to the Indus valley by sea in 711. Trade flourished from east Africa to China, but no country seems to have sought to dominate it. Africans, Arabs, Iranians, Indians, Malays, Indonesians, and Chinese all participated. Mangrove poles, ivory, and gold from Africa; cotton cloth and spices from India; spices from Southeast Asia; and pottery and other manufactured goods from China became well known in the Muslim cities of the Middle East, but no one conceived of the idea of following the trade to its sources and asserting political control over it by force of arms as the Portuguese and other Europeans did later. Seaport societies were typically multilingual and cosmopolitan, but no Muslim city became politically important as a seaport between 600 and 1500. Basrah, the intermediary trade center at the head of the Persian Gulf, is only an apparent exception. Its undeniable political importance in the seventh and eighth centuries derived not from maritime activities but from the migration of Arab tribes from the deserts of the peninsula to take part in the conquests.

rivers. Finally, there is the matter of river transport. As in the case of maritime trade, no sources survive that would permit an estimate of the boatloads of grain or

[This text has been suppressed due to author restrictions]

other goods carried per year on the Nile or the Tigris-Euphrates system. Yet, the largest cities in the Muslim world, Baghdad and Cairo, were supplied primarily by river. Baghdad received myriad shipments by sailing craft coming up the Tigris from the south and from rafts floated down the Euphrates from the north. River traffic northward from Baghdad was impractical, however, because of the swiftness of the current and general absence of favorable winds. The Nile was more congenial to transportation. Prevailing northerly winds made it comparatively easy to sail southward upstream from the Mediterranean to the region of the first cataract around Aswan. To go in the other direction, one simply floated downstream with the current. Located at

the juncture of the Nile and its delta, Cairo derived maximum benefit from this system. The only other river transport of note involves the rivers of Central Asia and Russia. The Syr Darya (ancient Jaxartes) flows from the Pamir Mountains of Tajikistan and Kyrgyzstan to the Aral Sea in Uzbekistan; the Amu Darya (ancient Oxus) drains the Hindu Kush in Afghanistan and similarly terminates in the Aral Sea. The Aral Sea, however, is landlocked. Though river trade on these substantial rivers was feasible, there is little to indicate that the volume of traffic was large. Trade on the Volga, Don, and Dnieper further to the west is another story. Scandinavian merchants sent furs, amber, and slaves southward by boat for exchange in Byzantine and Muslim territories. Byzantium garnered the lion’s share of this trade since the Don and the Dnieper emptied into the Black Sea, but tens of thousands of Islamic coins found in hoards in the Baltic Sea region attest to the vigor of trade with Muslim regions by way of the Volga and the Caspian Sea.


George Hourani, Arab Seafaring in the Indian Ocean in Ancient and Early Medieval Times, revised and expanded by John Carswell (Princeton: Princeton University Press, 1995).

Patricia Risso, Merchants and Faith: Muslim Commerce and Culture in the Indian Ocean (Boulder: Westview Press, 1995).

Aziz Suryal Atiya, Crusade, Commerce, and Culture (Bloomington: Indiana University Press, 1962).

G. R. Tibbetts, Arab Navigation in the Indian Ocean Before the Coming of the Portuguese: Being a Translation of Kitab al-Fawaid fi Usul al-Bahr Wal-Qawaid (London, 1971).

Auguste Toussaint, History of the Indian Ocean (Chicago: University of Chicago Press, 1966).

Alan Villiers, Sons of Sinbad: An Account of Sailing with the Arabs in Their Dhows, in the Red Sea, around the Coasts of Arabia, and to Zanzibar and Tanganyika: Pearling in the Persian Gulf: and The Life of the Shipmasters, the Mariners and Merchants of Kuwait (New York: Scribners, 1940).

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