Economic Causes of the Hundred Years' War: Trade, Wool, and Wine

The Hundred Years’ War was as much an economic conflict as a dynastic or territorial one. By the early 14th century the English and French economies were deeply intertwined, and disputes over trade, tariffs, the privileges of merchants, and the control of the Channel provided both crowns with a steady supply of grievances that could be invoked to justify war. The English economy was structurally dependent on the export of raw wool, and most of that wool went to the cloth towns of Flanders — Ghent, Bruges, and Ypres — which sat under French feudal suzerainty. The French economy, for its part, depended on the export of wine, much of it from the English-held duchy of Aquitaine. The two economies were mutually dependent and politically antagonistic; the political conflict of 1337–1453 was in part the working-out of that contradiction.

The standard treatment is Anne Curry’s economic chapters in The Battle of Agincourt: An Anatomy (2020) and the more general work of John Munro in the New Cambridge Medieval History, vol. VI (2000). The older work of Robert Boutruche, La Crise d’une société: Seigneurs et paysans du Bordelais pendant la guerre de Cent Ans (1947), is the classic study of the Aquitanian dimension.

The wool trade

The English economy of the early 14th century was heavily dependent on the export of raw wool. English sheep, raised in vast flocks on the great estates of the Cistercian monasteries and the major aristocratic houses, produced a high-quality wool that was in great demand on the continent. The principal market was the cloth-producing towns of Flanders, especially Ghent, Bruges, and Ypres, where the raw wool was woven into finished cloth and exported throughout Europe.

The wool trade was, in fact, the economic backbone of the English crown. The export taxes on wool were a major source of royal revenue. The English kings had long recognised the importance of the trade and had taken active measures to control it, including the establishment of staple towns — designated ports through which all wool exports had to pass. The first staple was established in 1313 by Edward I at St Omer, and the system was expanded and modified by his successors. The staple was, in effect, a piece of commercial coercion: it forced continental buyers to purchase English wool at a designated place, where the English crown could control the price and collect the duty.

The French crown, for its part, recognised that the wool trade was a vulnerability of the English crown and was eager to exploit it. By 1337 Philip VI was in a position to threaten English access to the Flemish market, and the disruption of the wool trade became a major source of friction between the two kingdoms.

The wine trade

Just as the English economy depended on wool, the French economy of the south depended on wine. The duchy of Aquitaine was the principal wine-producing region of medieval Europe. The wines of Bordeaux — the clairet that was the English drink of preference, the vin de Gascogne of the hinterland, the sweet wines of the Lot — were exported to England in vast quantities. By the early 14th century English per-capita consumption of wine was higher than at any subsequent point in the country’s history.

The wine trade was, however, a source of friction between England and France. The English kings, as dukes of Aquitaine, were theoretically responsible for the regulation of the trade; the French crown also claimed a role. The result was a long series of disputes over tariffs, the privileges of merchants, the location of staple ports, and the right of French merchants to participate in the trade. Bordeaux and Bayonne, the principal Aquitanian ports, were both under English sovereignty and dependent on French commercial networks.

The Flemish question

The Flemish cloth industry, centred on Ghent, Bruges, and Ypres, was the principal market for English wool. The Flemish counts were technically vassals of the French crown, but the cloth towns had their own interests and depended on English wool. The English cultivated the Flemish cities through subsidies and trade concessions throughout the war; the French response was direct political control of Flanders, achieved in 1384–1385 under Philip the Bold of Burgundy.

The French invasion of Flanders in 1328, shortly after the coronation of Philip VI, was a direct response to Flemish support for English merchants. The disputes over Flanders were a central thread of the war’s economic and diplomatic history: the Flemish cities were, in effect, the principal continental allies of the English crown, and the French conquest of Flanders in the 1380s was one of the more durable strategic gains of the Caroline phase.

The staple towns

The staple towns were a key institution of the English wool trade. The system, established in 1313 and modified several times in the next half-century, required that all English wool exports pass through a designated port, where they could be inspected, taxed, and certified. The original staple was at St Omer, but the location was changed several times — to Antwerp, to Calais, back to the continent — sometimes by the English, sometimes by the French.

The staple system was a major source of friction. The English crown used the system to control the wool trade and to extract maximum revenue; the French crown objected to the English control of a trade that was essential to the Flemish economy. The dispute over the staple towns was one of the immediate causes of the war, and the French seizure of the English-held territories in 1337 included the staple towns themselves.

The collapse of English credit

The economic consequences of the war were dramatic on both sides. The English war effort of the 1340s had been financed, in part, by the loans of the Bardi and Peruzzi banking houses of Florence, both of which collapsed in 1343–1346 after the failure of the wool tax. The collapse of English credit is one of the under-emphasised reasons the Edwardian phase ended where it did: Edward III was unable to finance the long campaigns of 1346–1347 and 1355–1356 by the normal means, and was forced to make peace at Brétigny in 1360 on terms more favourable to the French than he would otherwise have accepted.

The fiscal consequences for France were equally severe. The English chevauchées of the 1340s and 1350s devastated the agricultural and commercial base of the country; the Black Death of 1347–1351, by killing perhaps a third of the population, reduced the taxable capacity of the kingdom for a generation. The French crown of the 1350s and 1360s was effectively bankrupt, and the recovery of the Caroline phase was made possible only by the patient work of Charles V and his fiscal administrators in rebuilding the royal tax base.

The structural view

The economic causes of the war are too often subordinated to the dynastic and feudal ones, and that subordination is wrong. The wool trade, the wine trade, the staple towns, and the Flemish connection all contributed to a political situation in which the English and French economies were deeply intertwined but politically antagonistic. The war was, in this sense, as much an economic conflict as a dynastic or territorial one, and the economic disputes between the two kingdoms shaped the course of the war over the following century.

The economic dimension of the war is, however, only one of its dimensions. The dynastic dispute over the succession to the French throne, the feudal dispute over the homage for Aquitaine, and the long-running political question of the relationship between the two crowns are the other dimensions. The causes of the war are best read together.