The flag of the Spanish Netherlands was the same as in use by the Dukes of Burgundy, from which the Habsburgs inherited the Netherlands in 1482, despite the fact that Burgundy proper was ceded to France.
History
The Habsburgs, which had so far been powerful nobility in Austria and the Holy Roman Empire, acquired the Burgundian Netherlands when Archduke Maximilian married Mary of Burgundy. Their son Philip the Handsome became the first Habsburg ruler of the Netherlands in 1482. In addition, he married Joanna of Castile in 1496, the Infanta of Spain, which had just started to acquire lands in the New World. When their son Charles V acquired the throne of Spain in 1516, he became the first Habsburg ruler of an empire where the sun would never set.
The Spanish Netherlands as the Seventeen Provinces. As a result of the Dutch Revolt Zeeland (6), Holland (7), Utrecht (11), Guelders (13 and 17), Friesland (12), Groningen (14), Drenthe (15) and Overyssel (16) seceded to form the Dutch Republic. During long course of that war the north of Flanders (2), north of Brabant (8) and Maastricht (9) were captured by the Dutch Republic. The remainder was defended or recaptured by Spanish troops and would form the basis of what are now Belgium and Luxembourg. The green territory was the Bishopric of Liege, which was part of the Holy Roman Empire
The Spanish Netherlands had its capital in Brussels and consisted of 17 provinces which were quite autonomous. Charles' son Philip II (reign 1556-1598) faced the challenges of costly warfare against the Ottoman Empire in the Mediterranean and the rise of Protestantism in Northern Europe. He responded hawkishly by increasing taxes and the suppression of other religions. These were the main causes for the Eighty Years' War that started in 1568 and led to the declaration of independence of the Dutch Republic in 1581.
The aftermath of the Eighty Years' War (1568-1648)
The Spanish had consolidated control over an area that spans across present-day Belgium and Luxembourg. Bordered by a hostile Dutch Republic in the north and equally hostile and aspirational Kingdom of France to the south, Spain always needed to be prepared to defend its Netherlands. The once flourishing economy of Flanders was severely hampered by the exodus of protestant refugees and the Dutch blockade of the Scheldt, which blocked Antwerp's access to the North Sea.
Map of the Low Countries after 1648, with the Spanish Netherlands in yellow.
The rule of Philip's daughter Isabella (reign 1598-1621) and her husband Albert VII of Austria succeeded in pacifying the Spanish Netherlands by allowing a certain level of autonomy, which in turn marked the start of renewed economic growth and prosperity. The remaining decades of Spanish rule were marked by French invasions and the annexation of Flemish territories that currently are in France.
The War of the Spanish Succession (1700-1714) saw an Anglo-Dutch-Austrian alliance taking control of the Spanish Netherlands, passing control to the Austrian Habsburgs. Consequently, these territories were known as the Austrian Netherlands from 1714 until 1795, and would eventually emerge as the Kingdom of Belgium in 1830 after French (1795-1815) and Dutch rule.
Currency
The primary unit of account in the Spanish Netherlands was the Flemish Pound, which was derived from the Carolingian monetary system that had been in place since the 9th century. Similar to the British Pound, it was divided in 20 Shillings (Dutch: Schelling, French: Escalin), each of 12 Groats (Dutch: Groot, French: Gros). At that time, a Flemish Pound was worth half of an English Pound, 12 French Livres or 6 Dutch Guilders.
Although the Pound was the main unit of account, no coins were minted in that denomination. The most frequently used unit was therefore the Flemish Groat (French: Gros Flamand). The Groat was a silver coin of around 2 grams inspired by the Venetian Grosso. The Double Groat became known as the Stuiver in Dutch and Patard or Sol in French. The Groat itself was divided in 2 Liards (Dutch: Oord or Oort), which would remain a frequently used demomination for copper coins until the late 18th century. A Groat was worth 4 Duit, 8 Penningen, 12 Korten (French: Courtes) or 24 Myten (Mites).
Other small denominations
Braspenning: 2½ Groat
Peerdeken: ¼ Schelling or 3 Groats
Stoter: 5 Groats
Silver coinage
Patagon: a large silver coin worth 96 Groats. Similar to the Spanish Dollar, and worth 8 Reales.
Philipsdaalder or Écu Philippe: large silver coin first issued by Philip II in 1557. Initially worth 70 Groats but by 1620 equal to 100 Groats.
Ducaton: worth 120 Groats
Gold coinage
Noble: coin of English origin valued at 100 Groats. Also named Rozenobel.
Florin: imitations of the Florentine Fiorino d'Oro that became the Gulden. Depending on purity they were worth beteeen 40 and 56 Groats.
Albertin: valued at 2½ Florins or 100 Groats
Souverain: valued at 1 Pound, 6 Florins or 240 Groats
Ducat: originally a Venetian gold coin of 3.45 almost pure gold. In the Low Countries initially valued at 120 Groats, by 17th century 200 Groats.
Couronne au soleil: based on French Louis d'Or, originally a gold Écu of around 3.5 grams of 93% purity. Estimated at around 2/3rd of a Pound or 160 Groats.
The Spanish Netherlands section of the catalogue contains coins that are in name of the Spanish sovereign. Some provinces that were part of the Dutch Republic from 1581 still produced these coins for some years, usually because they were occupied by loyalist and/or Spanish troops.
https://en.numista.com/catalogue/spanish-netherlands-1.html
