Preface: For the ONE PIECE!!! This essay was co-written with ChatGPT.

In the early phase of European overseas expansion, Portugal is commonly regarded as one of the first states to pursue sustained maritime exploration. By the mid-thirteenth century, Portugal had largely completed the Reconquista within its territory. The Treaty of Alcañices in 1297 established a relatively stable border framework, and the succession crisis of the late fourteenth century concluded in 1385 with the rise of the Aviz dynasty. By the early fifteenth century, Portugal had entered a period of comparatively stable royal authority, with clearly defined borders and a consolidated internal political order.

This early consolidation of territory and monarchy was both an advantage and a structural constraint. Compared with kingdoms that could still rely on inland expansion, prolonged warfare, or territorial integration to generate new growth, Portugal’s smaller hinterland and population limited the effectiveness of such strategies. Under these conditions, outward expansion gradually became a more attractive option.

This constraint first appeared in agricultural conditions. The natural environment of western Iberia imposed objective limits on the stability and scalability of agricultural production. While sufficient to sustain the state, agriculture offered limited capacity to support sustained population growth and urban expansion. The fiscal base derived from land was therefore highly sensitive to war, famine, or trade fluctuations, leaving state finances relatively fragile.

In the absence of substantial agricultural surplus, craft production might have offered a path forward. However, medieval industrial competitiveness depended not only on technical skill, but also on scale, networks, and standardized production. Portuguese cities were generally small, guild structures relatively dispersed, and production oriented toward local or nearby markets. This made it difficult to develop goods capable of entering core European markets as indispensable commodities. Within existing trade systems, Portugal thus struggled to gain bargaining power or establish an irreplaceable commercial position.

The highly profitable spice trade from the East, in theory, held the potential to change this situation. In the medieval period, spices were both luxury goods and widely used in medicine and food preservation, combining high value with ease of long-distance transport. Yet Mediterranean intermediary trade long remained in the advantageous hands of Italian maritime republics such as Venice, making it difficult for western Iberian states to achieve comparable profits within established routes. Portugal was not excluded from participation, but typically entered on less favorable terms that made capital accumulation difficult.

In this context of marginalization within existing systems, Portugal was not entirely without options, but its internal alternatives were relatively limited. Compared with larger kingdoms such as France, which could rely on agricultural surplus and demographic expansion to build internal economic cycles, or Italian city-states that embedded themselves in high-value networks through finance and re-export trade, Portugal’s scale and geographic depth made such paths less feasible. External exploration therefore gradually shifted from being merely optional to strategically significant.

The 1415 conquest of Ceuta is often regarded as an important starting point in this process. Located on the southern shore of the Strait of Gibraltar, Ceuta was believed to be connected to trans-Saharan trade networks. Portugal initially hoped that by controlling this node it could access existing gold and trade routes. However, historians widely note that the defensive costs of Ceuta were high and the economic returns fell short of expectations. Trade networks proved to be attached not to the city itself but to flexible routes. This experience encouraged Portugal to shift its focus toward sustained exploration along the African coast rather than reliance on a single inland trade node.

Spain’s situation in the late fifteenth century differed from Portugal’s. The union of Castile and Aragon and the fall of Granada in 1492 marked the end of the Reconquista. State consolidation had just been achieved, and aristocratic, military, and religious forces remained highly mobilized. Spanish overseas exploration therefore arose less from economic marginalization and more from an existing expansionist momentum and the search for new resources.

Columbus’s voyage, originally intended to find a new route to Asia, instead reached the American continent. Subsequent Spanish expansion centered on territorial conquest, mineral extraction, and population control. The discovery of major silver mines greatly expanded royal finances, while over the long term in the sixteenth and seventeenth centuries also correlating with inflation, structural economic shifts, and increasing external dependence. Compared with Portugal’s strategy of integrating into trade systems through control of routes, Spain relied more directly on territorial rule and resource extraction.

If Portugal faced limitations in internal growth space, the Ming Chinese empire presented the opposite case. China possessed a vast and continuous inland territory, a mature agrarian system, and an economy capable of internal resource circulation. State finance depended primarily on land, population, and taxation rather than long-distance maritime trade. For an empire of this scale, foreign trade was not a condition of survival.

The official objectives of Zheng He’s voyages were primarily political and diplomatic, emphasizing the display of imperial authority, the reconstruction of tributary order, and the confirmation of regional hierarchy. Although these expeditions did influence regional commercial exchange, their organizational logic did not prioritize permanent bases, route control, or profit maximization. Within the Ming institutional framework, long-distance maritime trade represented higher uncertainty and lower administrative controllability. As state priorities shifted toward northern defense and inland governance, the contraction of maritime activity can be understood as a rational reprioritization within the system.

Against this background, Portugal’s gradual maritime advance along the African coast reveals its distinctive character. Fifteenth-century navigation conditions were extremely limited: longitude could not be measured accurately, ship durability was fragile, and voyages far from land carried extreme risk. Coastal progression was therefore both a strategy of risk control and a method of cumulative learning. Maritime exploration evolved from one-time ventures into repeatable, improvable processes.

The continuity of this long exploration depended on sustained state support. Portuguese royal authority in the fifteenth century possessed the capacity for mobilization and decision continuity, enabling long-term investment in ventures with high failure rates and low immediate returns. Failures were absorbed as experience, and losses treated as costs rather than endpoints. This institutional tolerance for error gradually transformed maritime exploration from a survival strategy into a tool for positional transformation.

As maritime routes increasingly demonstrated the ability to bypass established trade systems, Portugal gained direct access to the sources of high-value Asian goods. By mastering routes rather than relying on nodes, it acquired new leverage over pricing, profit distribution, and strategic initiative. In this process, Portugal moved from being a peripheral European kingdom to becoming a key intermediary within an emerging global trade network.