This post is the first part of a two-part series I have planned. It is about the history of trade on the western Indian Ocean and is based on reviews of a couple of books I read this year. Part two will look forward at possible developments in that region.

The books I'll be discussing here are Ocean of Trade by Pedro Machado and A Splendid Exchange: How Trade Shaped the World by William Bernstein. Rather than go over them one at a time, I'll be structuring this post thematically. It will start with a brief introduction to each book, then outline the geography and history of the western Indian Ocean. After that, I'll look at what it was like for merchants and trade goods to sail across it, at some institutional factors that promoted trade, and finally at some miscellaneous topics of interest.

Ocean of Trade covers a narrow window of time from approximately 1750-1850. It is also narrow in its geographical scope, focusing on trade between Diu in India and Mozambique in Africa (both of these were Portuguese colonies at the time). It comprises five chapters: the first two talk about how this trade was conducted, with regard to both business operations and actually crossing the ocean, then the final three focus on the preeminent commodities of textiles, ivory, and slaves. Textiles were particularly important as they were a medium of exchange in southeastern Africa, and Machado emphasizes that consumer demand from Africans was an under-appreciated driver of trade during this era.

These intersecting consuming passions for the goods of Africa and India thus brought ivory hunters, African long-distance traders and agents into close relation with Gujarati weavers, cloth brokers and bankers. Though separated by thousands of miles of ocean, the choices and decisions made by these protagonists influenced one another and created an inter-regional oceanic embrace made possible by Vāniyā merchants who played a key integrative role for these economies of the western Indian Ocean.

A Splendid Exchange is much broader in its scope, as it attempts to cover the overall history of international trade. It provides a very good longitudinal overview of its subject but of course can't go into the same level of detail as Ocean of Trade for any particular era. I found that it covered a lot of the same ground as The Ascent of Money and Sea & Civilization while having enough new material to keep me interested. While this book doesn't explicitly focus on the Indian Ocean, several key historical trade axes passed through that region, so it does get a lot of attention. As you'll see in the historical overview I share below, trade in the Indian Ocean has ebbed and flowed not just from improvements in technology, but according to global stability. As Bernstein writes,

Stable countries are trading countries.

One of the most salient features of the Indian Ocean is the monsoon winds. They are steady and predictable, and blow in opposite directions in the summer and winter. This makes them very well suited for sailing. Here are how Bernstein and Machado, respectively, describe them:

The huge Indian Ocean functions as a heat reservoir, remaining at approximately the same even temperature when the Asian land-mass heats up in summer and cools down in winter. Since heat produces low pressure and cold produces high pressure, the prevailing winds tend to blow from the area of high pressure (cold) to the area of low pressure (hot)—that is, more or less from the south in summer (the southwest monsoon) and more or less from the north in winter (the northeast monsoon)  ...
these seasonal winds, which enabled Greek traders to cross the Arabian Sea directly from Bab el Mandeb to India in a matter of weeks. The result was a flourishing of large, ethnically diverse hubs such as Socotra and the Malabar ports—polyglot communities where trade diasporas of many nations and races mingled


Beginning in November, the northeast monsoon built up, during which time ships from Arabia and India could leave the coast to reach African destinations as far south as Kilwa in a period of 30 to 40 days. Strong tropical storms in the eastern Arabian Sea in the months of October and November meant that the best times for vessels to sail from western India was in December when the monsoon had moved as far south as Zanzibar; vessels could then make the crossing in the considerably shorter period of 20 to 25 days.
The reversal in the wind(s) in April (the northeast monsoon having begun to break up in the south by March) signalled the start of the southwest monsoon, which was when vessels left the Southeast African coast for their return voyage(s) north to the Arabian Sea. However, between mid-May and mid-August there was an interruption when winds became “much too strong” for any sailing to take place. The choice for captains, then, was between making the homeward voyage either in the “build-up” of the southwest monsoon in April, or possibly at its “tail-end” in late August or September.

Basically, the prevailing winds in that part of the ocean come from the southwest in the summer and from the northeast in the winter. In addition to the monsoon winds, the strong west-to-east winds along the southern edge of the Indian Ocean (the "Roaring Forties") were also eventually useful to sailors as Bernstein notes:

The first system [of trade winds], taken advantage of by Columbus, and even more spectacularly by Magellan, blows from east to west in the tropical latitudes (or, more accurately, from the northeast above the equator, and from the southeast below it). The second system blows in the opposite direction—from west to east—in the temperate latitudes, most strongly between forty and fifty degrees latitude in both the northern and southern hemispheres

Other than the winds that provided historical sailors the means of getting around the Indian Ocean, its geography is also defined by its entry points. The most significant ones are rounding the Cape of Good Hope (from the Atlantic Ocean), the Bab El Mandeb (from the Red Sea, which provided access to the Mediterranean as well as the Hajj to Mecca), the Hormuz Strait (from the Persian Gulf, which connected with overland East-West routes through Baghdad), and the Malacca Strait (from the South China Sea and the Indonesian archipelago). There's also the Sunda Strait between Sumatra and Java; the preferred route of Dutch sailors was to use the "roaring forties" as a shortcut from the Cape of Good Hope to the Sunda Strait, where they set up Batavia (modern Jakarta) as the fulcrum of their trade in Asia. The Torres Strait into the South Pacific doesn't seem like it was relevant during the historical period considered in this post.  

As mentioned, A Splendid Exchange provides a broad historical overview of international trade.  I'll briefly summarize it here; the Indian Ocean is quite central in this history as it provided a water route between East and West. Bernstein refers to the "earliest axis of trade" as stretching out from Mesopotamia to Anatolia (the core of modern Turkey) in one direction and through the Gulf and along the coast to the Indus River valley in the other direction. As time progressed, the axis of trade across the Indian Ocean lengthened, with goods passing between Europe or the Middle East and East Asia during eras when there were stable empires at each end. For example, there was trade between the Roman Empire and Han dynasty China, and between the Abbasid Caliphate and Tang dynasty China. Keep in mind that it would have been rare for any individual to travel the whole distance (although Bernstein mentions a Roman trade colony in the vicinity of Pondicherry), rather, goods (silk, for example, was a luxury good in ancient Rome) would migrate from one entrepôt to another along gradients of demand.

Keeping in mind the entry points to the Indian Ocean discussed above, there were three popular East-West routes utilized in classical and medieval times. One went through Mesopotamia and the Gulf. Another went via the Red Sea (which was much more challenging to navigate due to shallows and contrary winds); Alexandria and Cairo benefitted greatly from this trade. Additionally, there was the overland route (i.e. the Silk Road—not really a single road but a network of oases, caravanserais, and mountain passes; a camel can carry around a third of a ton 30+ miles per day and can last 3 days without water, so rest spots were needed every 100 miles or so). This was especially the case when the Mongolian khans had brought Central Asia under unified political control; at other times travel by sea was easier. (This window of relatively easy land travel across Central Asia is also when the Black Plague spread. It reached the Genoese-controlled port of Kaffa—which had a big slave market that provided a lot of the Mamluk soldiers—on the Black Sea during a Mongol siege in the 1340s and from there quickly reached ports throughout the Mediterranean.).  

For centuries, these three routes were all under Muslim control. Bernstein writes that,

The early Muslim conquests essentially recreated the Pax Romana, but on an even grander scale. The Umayyad and Abbasid empires were in effect large free-trade areas in which old borders and barriers had been swept away, especially along the Euphrates River, since remotest antiquity the traditional frontier between the East and West. No longer were the three great routes to Asia—the Red Sea, the Persian Gulf, and the Silk Road—competing alternatives; rather, they were an integrated global logistic system available to all parties who recognized the suzerainty of the caliphate.

The European age of exploration was largely motivated by trying to get around this Islamic monopoly. A breakthrough came when Vasco da Gama reached the Indian Ocean by the other western entrance: rounding the southern cape of Africa. Something I learned from A Splendid Exchange was that da Gama had a good idea of where he was going (a quote I share below cites his navigational accuracy, with the assistance of a pilot acquired in East Africa), probably because earlier Portuguese travellers had visited various ports in the Indian Ocean (via the other routes) and written about them. An interesting what-if raised by Bernstein is that China had briefly made a show of naval force in the Indian Ocean only sixty-five years before da Gama's voyage. History might have gone very differently if Portuguese and Chinese fleets had encountered each other.

Given China’s advantage in maritime technology, the relatively low profile of its traders west of Malacca is remarkable. Only during the period between 1405 and 1433 did the Chinese intentionally flex their muscle in the Indian Ocean. Perhaps the inferior status accorded traders by Confucianism, which viewed merchants as parasites, steered the brightest and most ambitious away from trade and into the economically stifling Mandarin bureaucracy

As it turned out, Portugal was able to establish forts at critical harbours and choke points and win some naval engagements such as the Battle of Diu against an allied force of the Egyptian Mamluks and some Indian monarchies. In spite of their small population, they were thus able to establish a measure of control over trade in the Indian Ocean. They were succeeded by the Dutch and then the British, and A Splendid Exchange spends a lot of time talking about the East India Companies of those two nations. To round out this historical outline, here's how Ocean of Trade describes its more focused setting in what remained of Portugal's Indian Ocean colonies by the time the British were in the ascendancy:

By the seventeenth century, Gujarat and Gujarati merchant networks thus effectively operated as linchpins of trade in the Indian Ocean, and while their relative importance may have changed over time (in relation to Hadrami or Kutchi Bhātiyā merchants, for example), they played one of the most important integrative roles in its culture and economy as mediators of cross-regional contact and as facilitators of long-distance commerce.

This is a good reminder that even during European colonialism local communities in the Indian Ocean continued to have a large role and presence in trade there. The first Indian to receive a British knighthood was a trader from Bombay while it was governed by the East India Company, for example.

Moving on from the historical and geographical background, I'll spend a little time on ships and sailing on the monsoon seas. According to Machado, voyages from Mozambique to India (he says 3-5 ships per year plied this route out of Diu and Daman in the second half of the 1700s) lasted about a month at the start of the 19th century. Using the distance from this screenshot from Google Maps, that works out to an average speed of around 7 km/h (3.8 knots since 1 NM = 1.85 km).

V = D/T

Vasco da Gama crossed a narrower stretch of ocean (Kenya to Kerala) at about the same speed:

In only twenty-three days, they had flown across 2,800 miles of open ocean, missing their target, Calicut, by just seven miles. The world’s most brutal trading nation had “discovered” the secrets of the monsoon; the wolf had entered the sheepfold, and world commerce would never be the same.
This set the pattern for most subsequent European expeditions to the Indies. They left in late winter so as to take maximum advantage of the south Atlantic trade winds, then caught the summer monsoon across the Indian Ocean to arrive in India in September, just six months after departing Lisbon.

Most of the ships used by local trading communities in the Indian Ocean were some variety of dhow. Here's how Machado describes the ships used by the traders he writes about:

According to one source, kotias approximated closely “in general appearance, construction and rig … the smaller of the Arab baghla type, being a two-masted decked vessel with a high poop, [and] a raked transom counter”. The dimensions of “fine” kotias could be “from 40 to 80 ft in length between the perpendiculars or 70–100 ft overall”. They were two or three-masted, lateen-rigged vessels with covered decks, and had an average carrying capacity of 100–200 tons. Kotias sailed extensively throughout the Indian Ocean, and were particularly widely used in voyages to the Persian Gulf and the East African coast.

It does seem that the caravel ships that the Portuguese used had some advantages over dhows in maneuverability. As more centuries passed, ship technology continued to improve. Clipper ships (such as the Cutty Sark) could exceed 15 knots. Although still powered by the wind, they were no longer bound to the seasonal rhythms of the monsoons since they were able to tack into the prevailing winds. For this reason, they were widely used in tea/opium runs to Canton and Hong Kong in the Pearl River Delta region of China. Bernstein notes that clipper ships continued to be used even after steam power was available because they had an advantage on long routes (since they weren't limited by the need to refuel on coal). However, once the Suez Canal opened in 1869 (cutting the distance between London and Bombay almost in half), steam power had the definite economic advantage. Machado also notes how changing technology marked an end to the traditional Indian Ocean trading system based on the monsoon winds:

Notably, the growth of steamships in the long-distance carrying trades of the ocean exposed Indian (and other local) shipping to economies of scale they could not match, and lessened the reliance of seafarers on the winds of the monsoon system, while railway investments secured access to the markets of the subcontinent and imperialists sought to remake agrarian relations and establish new labour regimes.

(He also mentions competition from machine-made American textiles as a factor that drove disruption).

For a glimpse into that traditional system, A Splendid Exchange refers to medieval travel literature. From the tales of Sinbad to the writings of actual travellers like Ibn Battuta and Marco Polo, these accounts give a sense of what travel and trade was like then. Another account that Bernstein refers to is 'أخبار الصين والهند' from around 850 A.D. The crossing times that it provides for a journey between the Middle East and China are one month from Oman to the Malabar Coast, one month to cross the Bay of Bengal, 20 days around the Malay peninsula through the strait of Malacca, and one month to Canton. But due to the need to wait for the appropriate seasonal directions of the prevailing wind for each stage, the journey would have taken over a year in total. And a long distance journey like that would also typically involve changing boats multiple times:

Because merchants and captains preferred to ride the monsoons to and from their home port on an annual schedule, individual boats and crews tended to ply only one segment of the route year after year (if they were lucky enough to survive so many journeys).

Both of the books that are the subject of this post are about trade. One theme that I found interesting from them was about governance/institutional factors that could promote or stifle trade. Machado emphasizes the importance of trust between merchants:

Central to the structure and maintenance of mercantile life, and an essential factor in long-distance trade, was trust. Commercial exchange and agreements required confidence and shared expectations among merchants and agents that they would not be deceived or defrauded by the other party. Being able to trust a fellow merchant with investment capital or trade goods was particularly important in contexts where contract uncertainty existed or enforcement through formal legal institutions was either non-existent or ineffective. In short, trust was fundamental in enabling business and commercial transactions to occur both between merchants, their brokers and intermediaries and between them and the bankers on whom they relied for the provision of finance. Trust was intimately bound up with notions of reputability and creditworthiness that were integral to the functioning of merchant networks where a merchant’s “name” – whether they could be regarded as “creditworthy” and therefore men of “public credit” or not – was determined by prior experience of the individual and evidence of past behaviour. It was thus a highly significant aspect of economic exchange for merchant networks generally.

He feels that the merchants in Diu that he's writing about had some advantages when it came to maintaining trust. They had their traditional local institutions (mahajan) for arbitration but as a Portuguese colony they also had recourse to colonial legal institutions for dispute resolution. Confidence in the rule of law is good for building trust. Their trade generated a lot of customs revenue for the Portuguese authorities, so their needs and interests weren't something the governor or judge could ignore.

Although Vāniyā regarded certain aspects of Portuguese rule to be intrusive and overbearing, such as increases in customs rates in Diu and Daman or attempts to restrict their movement in Mozambique, they were willing to accommodate the official Portuguese presence because it provided an additional, or auxiliary, authority to which they had access as imperial subjects and which suited their needs. Particularly from the mid-eighteenth century, merchants were often explicit in asserting their rights and expressing their loyalty as subjects of the Crown in correspondence with Portuguese authorities. As such, they had full rights of appeal to the legal institutions of the state.

Another service that these merchants from Diu and Daman obtained from the colonial authorities was having one vessel per year designated (as a "barco de viagem") for naval escort and other privileges/protections.

In his book, Bernstein considers the governance and institutional factors (such as predictable and non-onerous taxes/duties and the rule of law) that led to the flourishing of the Sultanate of Malacca:  

What went right at Malacca? Its prosperity did not flow simply from its favorable location at one of the maritime world’s critical choke points, “at the end of the monsoons.” After all, the strait stretches several hundred miles along the Malay and Sumatran coasts and is far easier to control at its narrower Singapore end. Further, both the Malay side and the Sumatran side were studded with trading cities for centuries before Parameswara founded Malacca in 1400. Rather, the city’s wealth and prominence can be credited to the institutional genius of Parameswara and his heirs. Alone among the many trading cities that lined the strait, Malacca had found the answer to the question of whether to trade, raid, or protect. The Malaccans levied import duties less onerous than those prescribed by traditional Islamic custom, the maximum being just 6 percent (instead of the usual 10 percent), payable on imports from “the West”—that is, those brought by Indians and Arabs. If a Westerner and his wife were both settled in the port, they paid only 3 percent. Easterners —local Malays, Indonesians (including the Moluccans with their precious spices), Siamese, and Chinese—paid no formal import duties at all. From all imports, even from “Easterners,” were subtracted “presents” to the sultan and his lieutenants, estimated by Pires at a cost of 1 or 2 percent of cargo value. No trader, Eastern, Western, or local, paid an export duty. A reasonably solid, if informal, legal structure seems to have been in place, rivaling even the advanced common law of medieval England.

Another governance factor that gets discussed in A Splendid Exchange is the different approach to human resources between the Dutch and English East India Companies:

Over half of the million or so men who embarked from Holland’s wharves for the East never returned. In the words of the economic historian Jan de Vries, “It is hardly an exaggeration to say that the Company swept the city streets of beggars and the unemployed.” The low quality of these recruits would eventually be the Achilles’ heel of the VOC. By contrast, the EIC realized that it needed men who could sail, handle cargo, and fight to serve on its relatively small and undermanned Indiamen. The English Company selected only the most qualified applicants and granted them exemption from the Royal Navy’s press gangs.

Despite the earlier start and better financing of the Dutch VOC, it was eventually eclipsed by the English EIC.

Ivory was a major commodity covered in Ocean of Trade. I wanted to include some discussion of that trade in this post, since it was also mentioned in another book I reviewed this year, Harvesting the Biosphere:

The best available reconstructions of the ivory trade (Parker 1979; Luxmoore et al. 1989) show a relatively steady flow of around 100 t/year until about 1860, followed by a rise to more than 500 t/year just after 1900; the rapid plunge induced by World War I was followed by a brief rise, then another (World War II) slump, but the annual rate then rose steadily, to peak at more than 900 t by the late 1980s.

The numbers in Machado's book are significantly higher. He says that some years (in the late 1700s or early 1800s) the merchants he's writing about (on one route, compared to the global trade in the excerpt above) traded more than 300 tonnes of ivory. That represents over 3,000 elephants (assuming up to 50 kg per tusk—it's lower now). Assuming around 15 million African elephants in the late 18th century, this would be around 1% of the number that would die of natural causes in a given year (at a 50 - 60 year lifespan); however, Mozambique and the trade routes that fed into it only covered a portion of east Africa. I don't know which estimate of the historical ivory trade is more accurate.  

Yemen is a country I find kind of fascinating and have written about before. So I was interested in mentions of its history in these books. While the northern end (e.g. Alexandria) of the Red Sea route in and out of the Indian Ocean was much more prosperous than the southern end, there was often a port in Yemen that hosted some of this exchange such as Socotra, Mocha, or Aden. When the Portuguese empire was at its zenith, they failed to gain control of the entrance to the Red Sea (the Bab el Mandeb) so it remained open to competing traders. While Yemen was under Ottoman control for a period of time, it gained independence in the 1630s. Mocha was a thriving port in this era (and, yes, coffee was one of its exports). However, Machado writes that the tolerance for foreign merchants that trade depends had a shaky foundation:

This changed dramatically in the first quarter of the eighteenth century, however, particularly in the vibrant entrepôt of Mocha, as conditions became restrictive and exploitative in the 1720s. Legally, Vāniyās had been granted dhimmī or protected minority status (for which they paid a poll tax) as a “gracious act” by the imam in 1655–66 because normally this status was bestowed only on monotheistic communities in territories that came under Islamic law. While it offered imperial protection, the status involved restrictions on religious and sumptuary practice; some of these restrictions were overlooked but many were enforced strictly, resulting in an “inherent instability” in the status of Vāniyā merchants, traders and brokers. Moreover, in the late seventeenth century, the imam of Mocha forcibly converted or ordered the massacre – together with Jewish traders and merchants – of many Vāniyā.

Similar things happened elsewhere, too. Bernstein writes about the twilight years of the Tang dynasty:

In a scenario painfully familiar to modern Chinese in Indonesia, Indians in East Africa, and Jews nearly everywhere, the colonies of foreign traders on China’s coast became convenient scapegoats during tough times.

To close off this post, here's an old map I found of the Indian Ocean in 1940 (it's at least a century later than Ocean of Trade and also later than all but the last two chapters of A Splendid Exchange but it still shows a lot of the key ports mentioned) and a quote (from Bernstein's book) about the monsoon legacy:

Until the nineteenth century brought the clipper ship and steam, the seasonal dance of the monsoons—[from the] southwest in summer, northeast in winter—would dictate the annual rhythm of trade in the Indian Ocean.
An old map I found