17th century economic history is beyond me, but: yes, the Flemish wool export industry pretty much cratered in the early/mid 14th century.

By 1300, northern Italy and the southern Low Countries were the two most urbanized areas in Europe. Their cities faced a problem that more isolate urban centers like London and Paris didn't: they weren't self sufficient. Their "hinterlands" (a technical term!) could not supply each city with the raw materials for food subsistence and for their major industries. In the case of Flanders--especially Ghent and Ypres--this was particularly the case with wool. The economies of both cities were heavily oriented around the production of wool cloth for export, although internally they also enjoyed a (far smaller) market for new and secondhand fabric, new and secondhand clothing, other uses of fabric. They were also involved in the luxury cloth export market, but (a) so were other cities and (b) not to the extent of wool.

Through the 14C, the Flemish wool export industry took three big blows. Of course the cities took steps to reorient themselves, but as John Munro showed, even that had problems.

The first crisis occurred in the middle of an even bigger crisis. Around 1320, as the Great Famine hit the southern Netherlands harder than basically anywhere else in Europe (because all of northern Europe's food was coming from the Mediterranean ring, and it took the most time and effort to get food to that region; combined with the population density), the wool industry of Italian cities kicked into sufficient gear for them to be self-supplying as far as finished products went. Ghent and especially Ypres lost their Italian market.

The next problems came around 1337, as English-French hostilities kicked up a gear. Given the weird situation of geopolitics over the 100 Years' War, with multiple French crowns, England in France, everyone related, etc, it's no surprise that alliances were always fraught with the possibility of disaster. Nevertheless, the Flemish count's marriage to a French princess was pretty high on the list of things that did not make Edward III happy. So right away, wool exports from England to the Low Countries were legally limited and channelled through a few specific ports.

Although a lot of scholars point to 1337 as the major pivot point, that's not quite the whole story. Flemish aristocrats--especially merchants involved in importing wool from England to Flanders, which was an even more lucrative field than actual fabric production and export--were very keen to restore at least their own cities' relationship with England. And at least in the case of Ghent, it seemed to work for a time.

However, internal problems in the cities combined with England's war machine needing funding rolled like a snowball gathering size into the 1360s, which Munro cites as the biggest shock to Flemish wool cloth. England's new export taxes and shifting patterns of who was allowed to export at all made the purchase of English raw wool basically cost prohibitive for Flemish buyers. This was utterly disastrous for Ghent, Ypres, and their port city Bruges, and it played into the civil wars between various textile-related guilds (late medieval Ghent is usually considered the most guilded-up and guild-powered city in Europe).

Now, rich people weren't about to give up their riches and the prospect of future riches without a fight. So a couple things happened. First, the small and beleaguered group of fabric-producers who had already begun working with Spanish wool (a disaster! unthinkable!) in the mid-14C expanded slowly but surely. When you talk about the Flemish wool industry in 16C (so I would presume also 17C?), it's basically Iberia powered. Second, the Low Countries cities oriented themselves more towards the Baltic/German Hansa cities as far as exporting went. Third, to respond to Italy and the England developing their own "cheap wool cloth" industries, Ghent and Ypres moved heavily into the luxury wool market.

None of these would quite recapture the glory days, but it definitely kept the cities chugging along in the international textile industry--just in an altered form, on a smaller scale, and with a lot more susceptibility to piracy due to having to import wool from farther away.

Modern Netherlands

Flanders

/u/Thucideswasawesome bls acknowledge the glory of the Spanish Netherlands .... ;_;

More seriously though, there were significant shifts in patterns of trade, relationship, and politics in the Low Countries under Burgundian rule. Wool and cloth were extremely important commodities, in 14th century England wool exports accounted for up to a third of its GDP (see, for example, Prak's Early Modern Capitalism).

Here government policy can see-saw depending on economic and political circumstances. For example, in the 1400s-1600s Low Countries where they needed wool imports but relied on cloth exports, there tended to be import duty exemptions for wool, but high import duty on cloth. In England, there were attempts to levy export duty on wool and introduce high tariffs against cloth imports, to encourage domestic cloth production. This is exactly what Henry VII did in the 1480s as reprisal against Burgundy's support of the rival Yorks: the protected wool trade that was limited to Calais was subjected to high duty both to punish Burgundian Netherlands and to encourage English cloth industry. This ended up having ruinous short-term impact on both sides, forcing Henry VII and Philip IV of Burgundy (Philip I of Castile) to sign the Intercursus Magnus agreement in 1496, but the long-term trends were irreversible. From the reign of Edward III to the reign of Henry VIII, wool exports declined from 34,760 sacks a year down to 1,136 sacks a year; while cloth exports rose from 2,483 sacks to 172,117 sacks. Comparing the two eras is important for reasons I shall give below.

That was not the first time English embargo led to ruin in Flanders. In 1270, Countess Margaret II of Flanders (and of Hainaut), demanded payments from Henry III of England for the support she had given them against Simon de Montfort's rebellion. Henry declined, and Margaret confiscated English properties in Flanders. England retaliated. However, the former is worth much more than the latter, thus Henry resorted to embargo of wool for leverage. Yet English merchants smuggled their merchandise to Flanders, and the situation wasn't as dire as in 1336 when England had greater control over her own embargo, as wool export trade had concentrated in London. That year may ring a bell: it was just around the time the 100YW was starting. French king Philip VI (the Fortunate) supported exiled Scottish king David II against the ambition of England, leading to naval warfare in 1336, re-directing a fleet he had built for a Crusade into naval action across the English Channel. Not unreasonably, England's Edward III was alarmed and prepared for the worst. Overlapping spheres of English and French influence in the Low Countries led to Edward using English wool exports once again as a means of leverage and punishment. He succeeded in obtaining the support of Brabant, Guelders, and Cologne, but Flanders under control of a pro-French faction had to suffer through the embargo.

And indeed, the textile industry was supremely important to major cities in Glorious Flanders. To quote Nicholas' Economic Reorientation and Social Change in Fourteenth-Century Flanders,

The Flemish economy had weaknesses in the thirteenth century which continued to afflict it during the fourteenth. Foremost among them was over-dependence for capital formation upon a single industry, fine woollen textiles. Save perhaps at Ghent, this trade was less tightly controlled by patrician dynasties than was once thought. .... The textile industry provided mass employment for more than half the population of Ghent and Ypres, and two fifths of that of Bruges depended directly upon clothmaking.

And more precisely, due to the development of trade and low quality of local wool, imported wool was very important to the textile industry.

Fortunately for the Glory of the Glorious Spanish Netherlands, in the time frame you are interested in, Spanish wool exports were starting to become prominent. This relationship was encouraged by successive rulers, especially as the House of Habsburg came to rule both Spain and the Low Contries. As said in Bowden's Wool Supply and the Woollen Industry,

English wool had been unsurpassed for fineness in the Middle Ages, but as its quality deteriorated so did Spanish wool gain in estimation. Already in the early sixteenth century it was noticed that English wool was losing its reputation for fineness to Spanish wool, and by the end of the century the latter was almost certainly superior. The decline which occurred in the English wool export trade during this period was undoubtedly largely due to the pressure of home demand and the relatively high price of English wool in the foreign market, but a not unimportant factor in the decline of overseas demand for fine wool may well have been the deterioration in the quality of the English fine-wool supply

Starting from the early 1600s, Spanish wool started to become the dominant supply of wool in all of France, Italy, and the Low Countries.

So, where to learn about all this? Poooof ..... in the style of the most genuine Flemish woof-shrug you have ever heard ..... two good books are probably Nicholas' Medieval Flanders and Keen's England in the Later Middle Ages.

Finally, to circle back to my beloved Castile, the sheep herders' association the Mesta was a key political player, organized in the 13th century as a means of empowering and controlling the wool business. Castile was the backbone of the Spanish empire, Medina was its financial center, and the Mesta was its richest constituent. Is it a wonder that Don Quixote liked to say, I am but from a humble sheep herders family? As they say in Spain, do not mix the churras and the merinas.

Glorious Spanish Netherlands ..... ;_;