In a recent essay in this journal,Footnote ¹ Geoff Wade suggested that between c. 900 and 1300 maritime trade influenced political and social evolution across Southeast Asia far more extensively than generally has been recognised. Redeploying the ‘Age of Commerce’ thesis that Anthony Reid originally developed for the period 1450–1680, Wade argued that between 900 and 1300 as well, commercial impulses from beyond Southeast Asia provided the prime mover, the critical agent, the indispensable stimulus to local evolution. A ‘number of changes external to what is commonly referred to as Southeast Asia, impacted the region and provided an environment where maritime trade boomed, and this trade boom induced political, social and economic changes throughout the region’.Footnote ² Thus Wade termed the era between the start of the tenth and of the fourteenth century an ‘Early Age of Commerce’.

In support of his thesis that Southeast Asian vitality issued directly from rising market demand in China, the Mideast and India, Wade used largely secondary sources in imaginative and perceptive fashion to trace the impact of Chinese and Indian Ocean trade networks on a variety of Southeast Asian developments: the spread of new religions, the movement of political centres from the interior to the coast, political integration, rapid population growth, monetisation, cash cropping, new ceramic and textile industries, and novel modes of domestic consumption and mercantile organisation.Footnote ³ No one, so far as I know, had inventoried these ostensibly disparate phenomena across Southeast Asia before 1300, much less linked them to a common maritime dynamic.

And yet if Wade's essay offers a welcome, refreshingly integrated overview, his reliance on Reid's Age of Commerce model and his emphasis on regional unity and uniform etiology also carry certain risks. My purpose in this short commentary is to offer, in necessarily cursory fashion, some theoretical perspectives that both complement and complicate Wade's approach.Footnote ⁴

One danger in applying to an earlier period a theory developed for the fifteenth to seventeenth centuries is that it risks mechanistic duplication and chronological conflation. Reid argued that maritime trade was seminal to the dissemination of textual religions – Islam, Christianity, Theravada Buddhism, and to a lesser extent, Neo-Confucianism – during what he terms Southeast Asia's ‘religious revolution’.Footnote ⁵ Wade claimed that international commerce spread new religions between c. 900 and 1300 as well. However, the pre-1300 evidence is less strong, and such evidence as we have comes not from the period as a whole, rather from the thirteenth century. This weakens the utility of 900–1300 as a coherent category – at least as regards religious change – and suggests that the thirteenth century might be assimilated more profitably to Reid's subsequent Age of Commerce. For example, although since at least the ninth century Muslim traders from the Mideast had congregated in Chinese and Southeast Asian ports, the conversion of Southeast Asians themselves to Islam seems to have begun fitfully in north Sumatra only in the thirteenth century and did not become regionally significant until the fourteenth and more especially the fifteenth and sixteenth centuries.Footnote ⁶ Likewise, in the Khmer empire Theravada Buddhism began to eclipse Hinduism/Mahayana Buddhism only after 1220 or 1250.Footnote ⁷

Following Reid, Wade also suggested that between 900 and 1300 rulers shifted their capitals from the interior towards the coast in an effort to control maritime trade and thus to centralise patronage. In Java the post-920 political shift from the southcentral interior to the Brantas basin did respond, at least in part, to the lure of the China trade. Likewise in Vietnam, as John Whitmore recently has shown, the Tran Dynasty (1225–1400) developed a secondary capital in the commercially vibrant Red River delta. Yet the Tran's primary base remained at Thang Long in the interior.Footnote ⁸ Moreover, what I term the ‘charter’ states of Upper Burma and Angkor stood firm against maritime pressures well into the fourteenth century. It was only after 1369 that Pegu, after 1351 that Ayudhya, and after c. 1440 that Phnom Penh became major regional centres at the expense of imperial centres farther inland.Footnote ⁹

As regards monetisation, cash cropping, and handicraft and mercantile innovation, our data between 900 and 1300 are simply too meagre to say with any confidence whether these shifts adumbrated the type of changes Reid documented between 1450 and 1680.Footnote ¹⁰

Arguably, however, the danger of chronological conflation is less than that of overstating pre-1300 geographic uniformity. In a word, maritime primacy between 900 and 1300 works admirably for some sectors of Southeast Asia, but less well for others.

Few scholars, I think, would doubt that Wade has captured effectively the principal economic dynamic in thinly populated coastal polities with limited agrarian resources, polities such as Champa in what is now central Vietnam, Tambralinga and Kedah in the Malay peninsula, Srivijaya and other port states in eastern and northern Sumatra, and coastal enclaves in Borneo. In Java too, as Jan Christie, the leading scholar of early Java, has shown, trade with South China and the eastern archipelago between c. 900 and 1400 contributed not only to an eastward shift in capitals and the opening of new ports, but to commercial intensification. Much of Wade's evidence for commercial agriculture, monetisation and new forms of consumption in fact derived from Christie's work on East Java.Footnote ¹¹

The problem is, however, that Wade favoured a one-directional stimulus-response model: Chinese and Indian Ocean demand compelled Southeast Asian adjustments. But in fact external and domestic elements often joined in complex synergies, and to dwell exclusively on the former elements is, in my opinion, to posit an implausible degree of indigenous inertia. To some degree this caveat applies even to labour-scarce realms like Srivijaya, where improved political coordination and/or an increase in local population could enhance entrepôt efficiency, the supply of local exports (forest and sea products and minerals), and the demand for Chinese and Indian imports. This concern is more obviously germane to Central and East Java, Upper Burma, Angkor and Đại Việt — relatively well populated areas where the political economy focused more substantially on agricultural resources and manpower, and where population growth and political consolidation from c. 900 to 1300 were heavily influenced by domestic factors.

Thus, for example, my reading of Javanese historiography argues that between c. 900 and 1300 the major agents of economic expansion were Hindu/Buddhist temples, to which kings and lesser lords transferred tax rights on specified lands. By collecting and marketing produce and by marshalling bonded labour, such institutions built new water control systems, bridges and roads and converted shifting cultivation and jungle to extensive wet rice acreages. Even after Javanese elites began investing local surpluses in luxury imports rather than temples, land reclamation and population growth continued under religious as well as lay auspices.Footnote ¹²

To be sure, overseas contacts could accelerate and rechannel these processes. Indirectly, they aided expansion by providing those systems of architecture, ritual and cosmology – Hindu and Mahayana – on which temple networks in Java and other charter states ultimately rested. More directly, imported techniques and metals assisted Javanese artisans, while Indian and Chinese textiles, ceramics and other handicrafts encouraged commercial production. To follow Peter Boomgaard, the latter stimulus operated on two levels. On the one hand, some peasants eager to buy cheap foreign imports (and at the same time to meet demand for cash taxes) brought surplus goods to market for both domestic and overseas sale. On the other hand, in order to obtain exotic foreign handicrafts, perfumes and spices, secular and lay elites collected crops for export.Footnote ¹³ Thus the Javanese kingdom of Majapahit sent rice and foodstuffs to Maluku, and black pepper, safflower dye, medicinal herbs to China. Chinese cash and imitations of Chinese coins facilitated transactions on both levels. To obtain prized goods for their own use and for export, Java's rulers also sought repeatedly to dominate overseas ports. This hybrid agrarian-commercial orientation may help to explain why, alone among major agrarian states, Majapahit survived the fourteenth-century commercial expansion that weakened Upper Burma, Angkor and Đại Việt.

Yet, on present evidence, the proliferation across the Javanese countryside of permanent and periodic markets – to which peasants and professional traders fed rice and other foodstuffs, livestock, indigenous textiles and pottery – benefited far less from maritime stimuli than from local population increase and forest reclamation. A very modest, if indeterminate, portion of rural production seems to have entered the market, and of that only a fraction went overseas. Domestically generated agrarian extension and intensification were primarily responsible for the pattern whereby existing villages expanded, new villages devolved from older settlements, and commercial exchanges multiplied across the countryside. Inscriptions from the late first and early second millennia refer to burgeoning domestic markets. In turn, local commerce could spur population growth insofar as such marts provided alternate sources of income and aided food distribution in rice-deficit areas. By extension, better nutrition could enhance female fertility and lower child mortality.Footnote ¹⁴ To 1400 there is no evidence that more than a small percentage of Java's population depended for their livelihood on specifically maritime exports, imports or markets — which alone therefore seem inadequate to explain a general agrarian/demographic upsurge between c. 900 and 1300/1400 and an associated expansion in state resources.Footnote ¹⁵

Such a judgement is yet more secure for Upper Burma. As reconstructed by Michael Aung-Thwin, G.H. Luce and Than Tun, economic expansion in the empire of Pagan centred on Buddhist temples to which wealthy laymen donated extensive acreages and unfree cultivators. Like their Javanese counterparts, such institutions sponsored improvements in agrarian technique, novel forms of labour control, new waterworks and forest reclamation. Having expanded between c. 900 and 1100 in ‘heartland’ districts (hkayaings) northeast and south of Pagan, from the late twelfth century agrarian reclamation moved into frontier areas (taiks) west of the Irrawaddy and south of Minbu. During the thirteenth century reclamation continued, albeit at a more modest pace. In combination, hkayaing intensification and taik colonisation permitted and reflected sustained demographic vitality, perhaps too an increase in per capita productivity, along with expanded local markets for land, labour, foodstuffs and materials. In short, here even more clearly than in Java domestic spurs were central to commercial intensification and overall growth. According to Aung-Thwin, the leading Pagan scholar, it was the development of irrigation works in agricultural basins over 650 kilometres from the coast ‘that enabled the kingdom of Pagan to expand beyond the dry zone of Upper Burma in the first place’ and to dominate the maritime south.Footnote ¹⁶

Again, I have no desire to minimise maritime influences. Although not cited by Wade, Guy Lubeigt recently has argued that the Irrawaddy transmitted Indian Ocean commercial impulses to Pagan, whose elites, starting with the king and the royal family and followed by local and foreign merchants, derived profits from trade sufficient to finance at least part of their religious constructions.Footnote ¹⁷ Aung-Thwin concurs that coastal trade and luxury imports supplemented agrarian income and helped to pull Pagan's armies into the south as early as the eleventh century. Yet evidence for rice or agrarian exports from Pagan is far more meagre than from East Java. On the whole, Aung-Thwin concludes, Upper Burma ‘had little need for external trade’, which played only ‘a minor role’ in the overall economy and society.Footnote ¹⁸

Angkor resembled Java and more especially Pagan in key respects. In the early eleventh and late twelfth centuries foreign trade provided the Khmer elite, like its Burmese and Javanese counterparts, with valued revenues and prestige goods and helped to direct imperial expansion, in this case in the upper peninsula and against Champa. Like Pagan, however, Angkor was located at some distance from the commercial coast in an interior dry zone where a self-sufficient agrarian dynamic – substantially reliant on religious temples for labour control, technical knowledge and investment in reclamation and water control – defined the essential rhythms of economic life. Indeed, Cambodia's charter-era florescence came only after the economic centre of gravity shifted from the coast to the interior. According to Michael Vickery, after the seventh century Cambodia's ‘economy was almost entirely agrarian’.Footnote ¹⁹ At its peak, Angkor was probably the world's most extensive low-density city, covering 1,000 square kilometres with over half a million inhabitants. A vast water management and irrigation network supported three distinct, yet interconnected zones for control, storage and distribution on which not only a sector of agriculture, but the city's moats, pools, architectural and residential infrastructure depended. Until climatic shifts and technical weaknesses overwhelmed it after 1300, this massive system afforded Angkorian civilisation the stability necessary to survive frequent intra-elite conflicts.Footnote ²⁰ Even under Suryavarman I (r. 1001–1050), the king most closely associated with Angkorian commercial expansion, trade remained secondary to developing and maintaining Angkor's agrarian base. Under his successors an internal orientation became yet more pronounced.Footnote ²¹ In Claude Jacques' succinct formulation, ‘Everybody agrees that the Angkorean [sic] economy was based only upon agriculture.’Footnote ²²

As for Đại Việt, Whitmore has done more than any scholar to explore growing cultural and commercial ties to the coast and to South China during the Ly (1009–1225) and more especially the Tran (1225–1400) Dynasties. But in concluding a recent survey of Đại Việt's maritime links, he wrote:

Much as in Pagan, Angkor and Java, Whitmore suggested, the prosperity to c. 1200 of that mid-river core centred on Buddhist temples and estates, which concentrated labour and technical resources and spearheaded the opening of interior foothills to cultivation. After c. 1200, moreover, the increased salience of the coast in Đại Việt's political economy reflected the laborious and technically difficult, but economically rewarding conversion of rich deltaic swamplands to agriculture as much as, if not more than, it reflected expanding maritime trade ties to China. At the same time in Đại Việt as in other charter realms, such maritime trade expansion as did occur benefited not only from external dynamics, but from the augmentation in market supply and demand that local population increase made possible.Footnote ²⁴ In assessing the pre-1300 role of maritime trade, note finally that as in Burma, Siam/Cambodia and Java, so too along the mainland's eastern littoral it was only after 1300 that the political centre of gravity shifted from the agricultural core towards the commercial coast.Footnote ²⁵

After evaluating in methodical, theoretically informed fashion the relative contributions of maritime and internal stimuli, Boomgaard also has concluded that before 1400 ‘economic and environmental changes in Southeast Asia were set in motion almost entirely by internal developments (mainly climate fluctuations, disease patterns, war, and [domestically generated] population growth)’, rather than by extra-regional commercial forces.Footnote ²⁶

In the more densely settled sectors of Southeast Asia, especially on the mainland, the general pre-1300 relation between domestic and external stimuli therefore may have resembled that in western Europe and key sectors of South Asia and China. Between c. 900 and 1300 the latter regions also enjoyed unprecedented vitality — demographic, agrarian, commercial and political. Yet long-distance trade was merely a secondary, acceleratory factor. Of course, to recall my own introductory admonition, in attempting broad geographic comparisons, one must guard against artificial conflation. But if my analysis has any merit and if the sophisticated historiographies of Europe, China and so forth may be trusted, notwithstanding obvious differences in scale, the parallels between Southeast Asia's agrarian cores and these other agrarian regions are, to say the least, intriguing.

Writing of Europe's high medieval expansion c. 950–1350, for example, Robert Lopez observed, ‘Even as demographic growth was a prime motor of agricultural progress, so agricultural progress was an essential prerequisite of the Commercial Revolution … it is proper to say that the revolution took off from the manor.’Footnote ²⁷ ‘To put the circulation of money before agricultural development’, wrote Robert Fossier, is ‘to put the cart before the horse’.Footnote ²⁸ According to Arlette Higounet-Nadal, medieval French rural overpopulation, the result of agrarian progress, was ‘certainly the motor of urban development’ and trade.Footnote ²⁹ In R.I. Moore's words, the commerce and ‘the cities of medieval Europe “grew out of” the countryside’.Footnote ³⁰ While emphasising the unique ability of ever more extensive long-distance trade, extending to the Mediterranean and the Levant, to create windfall profits and to promote specialisation and efficient resource allocation, Michael McCormick concurred that early European commercial vigour drew primarily on agrarian productivity.Footnote ³¹ The powerful feudal monarchies of the high medieval era battened on this economic expansion, and associated fiscal, military, archival and cultural innovations.Footnote ³²

China's so-called First Commercial Revolution 800/900–1300 yields to similar analysis. Although maritime trade stimulated coastal cities and interregional trade and provided the beleaguered Song state with much needed revenues, there is general agreement that Song vitality derived primarily from the colonisation of Central and South China with its vast rice potential. Whereas for centuries China's population had grown very slightly, if at all, between the eighth and eleventh centuries it more than doubled, especially in the middle and lower Yangzi. Along with migration from North China and government incentives, the key elements in this boom were the opening of private estates capable of marshalling labour for large-scale reclamation and irrigation; improvements in cultivation technique; the introduction of hardy, quick-ripening rice strains from Champa; the dissemination of advanced hydraulic technology; and the creation of ever more ramified inland and coastal-shipping networks along which surpluses could move to market. Grain sales freed regions and producers to specialise in non-subsistence crops, in raw materials and in diverse manufactures. Commercial intensification and the sheer increase in the size of the consumer population also favoured new credit procedures, monetisation and retail specialisation. A broader, more mobile, more literate provincial elite, with commercial access to printed texts, in turn provided a social foundation for the unprecedentedly routinised, literate, permeative, examinations-based political order of the Song. In this multifaceted economic and social transformation, rising overseas commerce played a valued, but subsidiary role. This was true even in Chinese coastal regions whose involvement in maritime trade exceeded that of Pagan or Angkor.Footnote ³³

In South Asia in this period, long-distance trade, both overland and maritime, arguably was more critical to urbanisation and state formation than in much of Europe or China; while the political-cum-economic contribution of Inner Asian conquest elites lacked entirely a West European analogue. Suffice it to say, however, that across much of South Asia (particularly northwest India and the Deccan) as in Europe, China, and the more densely settled parts of Southeast Asia, the principal source of economic and commercial strength between c. 900 and 1300 was agrarian-cum-demographic expansion.Footnote ³⁴

If, as the Early Age of Commerce thesis argues, Southeast Asian vitality in these centuries derived overwhelmingly from extra-regional inputs, explaining correlations with other Eurasian areas poses no particular challenge. Maritime routes simply transmitted to Southeast Asia a dynamism that originated in China and India and, more indirectly perhaps, in medieval Europe and the Levant. But if economic expansion in key sectors of Southeast Asia had a primarily or substantially local root, three questions immediately arise: (a) Why did growth correlate in Pagan, Angkor, Đại Việt and Java, whose agrarian economies had no significant contact with one another?; (b) Why did economic and political vitality in these same regions correlate with Srivijaya and parts of the archipelago that relied overwhelmingly on maritime trade?; (c) Why did economic/political vitality in mainland Southeast Asia and Java correlate with trends in China, South Asia — and most curiously, in distant Europe?Footnote ³⁵

These are tremendously complex issues to which, in concluding this brief note, I can proffer only schematic answers.Footnote ³⁶ Part of the answer may have involved synchronised disease immunities, which were aided by maritime exchange but which also had their own dynamic. In the late first and early second millennia, modest cumulative population growth around much of the Eurasian perimeter – including western and northern Europe, South China, lowland Southeast Asia, Japan and perhaps South India – joined closer contacts with long-settled Eurasian cores to convert infrequent but extremely lethal epidemics, chiefly smallpox and measles, into endemic diseases of childhood. Once a disease has become endemic, universal childhood exposure precludes the horrendously destructive virgin-soil effects associated with smallpox in the New World and Oceania or with the Black Death in Europe. This would have favoured coordinated demographic and agrarian vitality between c. 800 and 1300 in far-flung Eurasian regions where trade-assisted exposure to foreign disease was most common and where populations needed to sustain local chains of endemic infection had become sufficiently dense.

A second explanation for intra- and extra-regional synchrony is the roughly coordinated opening of new agrarian zones. In post-Roman Europe and post-Han China imperial collapse, by empowering ‘barbarians’ from beyond the frontier, encouraged a gradual shift in the political centre of gravity to potentially highly productive but hitherto neglected agricultural frontiers, from the Mediterranean to Northwest Europe and from North to South China. New frontier environments then called forth innovative agrarian technologies along with new manorial systems. Although Southeast Asia and South Asia lacked an antecedent imperial collapse, those regions also saw (albeit in certain cases at a somewhat later date) the opening of fresh ecological zones, together with more efficient systems of agrarian and labour organisation.Footnote ³⁷ What is more, in mainland Southeast Asia, China and South Asia alike, interventions by mobile warriors from beyond the frontier – Tais, Jurchens, Mongols, Turkic peoples, Yadavas and Hoysalas – redrew the political map while in some cases accelerating commercial or agrarian expansion.

Third, closely related to ecological shifts and perhaps most decisive was the so-called Medieval Climate Anomaly c. 850–1250/1300, which assisted agriculture in much of Southeast Asia, South China, South Asia and northern Europe alike. Precipitated by changes in solar radiation and by oscillations in the heat economy of ocean currents, the Medieval Climate Anomaly (also known as the Medieval Warm Period) contributed to the rapid demographic and economic growth characteristic of the European high middle ages by extending the growing season, reducing excessive late summer rains, and drying rich bottom lands. But, ironically, this same period of hemispheric warming as helped cultivation in northern Europe by ‘drying it out’, aided agriculture in parts of Southeast Asia, South Asia and South China by strengthening regional monsoons. This it did by increasing water vapour in the tropical atmosphere, by swelling vegetation-dependent convection, and most critical, by raising spring–summer temperatures in the interior of Asia and thus magnifying the land–sea thermal contrast on which monsoons rely. The ensuing increase in the strength and reach of seasonal rains enhanced cereal production, often dramatically, in hitherto arid zones of South Asia, in much of South China, in East Java, in northern Vietnam and in those interior dry zones where Pagan and Angkor were based. Hence, in part, the coordinated opening of new agrarian frontiers. The Medieval Climate Anomaly allowed considerable temporal (not to mention regional) variation, but as a whole it was reasonably distinct from both earlier and later climatic regimes. It can hardly be accidental that dry-zone Pagan and Angkor as well as early Đại Việt began to prosper with the onset of the Medieval Climate Anomaly and collapsed with the end of that regime and the onset of appreciably drier conditions in the fourteenth century.Footnote ³⁸ The post-1350 political shift from interior to coast in what are now Burma/Myanmar, Thailand and Cambodia responded both to commercial lures and to the fact that the coast enjoyed higher rainfall. In Europe and China, and to a lesser extent South Asia, calamitous weather in the fourteenth century also was associated with severe economic, demographic and political upheavals.

Although these three factors – new disease patterns, the ‘barbarian’-aided opening of new ecological zones and climate shifts – were closely intertwined, in many contexts climate may have been primary. By magnifying agrarian output and population, the Medieval Climate Anomaly helped to push local peoples over the threshold needed to convert epidemic diseases to endemicity, accelerated colonisation and encouraged mobile warrior groups to enter sedentary spaces. In the eleventh to thirteenth centuries more ramified commercial and cultural ties to settled populations provided Inner Asian cavalry on the borders of China and India, and Tai warrior bands in Southeast Asia, with the cultural capital needed to rule agrarian states. At the same time, by enhancing demand and supply in one region after another, coordinated population growth across Eurasia powerfully boosted long-distance trade, both overland and by sea. Insofar as Southeast Asian products commanded high prices in China and India, and insofar as all East–West maritime intercourse – luxuries and germs included – flowed through Southeast Asia, global contacts both stimulated Southeast Asian commercial production and accelerated disease domestication. In heavily settled areas, maritime trade thus reinforced, and in some measure reconfigured, a prosperity that derived more basically from climatic amelioration, local population increase and frontier reclamation.

In sum, maritime trade does indeed seem able to explain economic, and by extension political, vitality between c. 900 and 1300 in Champa, the peninsula and much of the archipelago, although even in these areas one must treat carefully the interplay between local demographic/political forces and foreign demand. But in Central and East Java and in mainland cores, economic rhythms were governed to a more substantial – if still unquantifiable – extent by internal processes that, at first glance, appear loosely comparable to those in other agrarian sectors of Eurasia. These considerations suggest that before 1300 Southeast Asia not only received from afar, but also helped to generate historical dynamics fundamental to Old World evolution.