Flag of the Duchy of Nassau (1806-1866). Orange and blue are also the colours used by the royal family of the Netherlands who are originally from Nassau.
History
The town of Nassau was founded in 925. Although its rulers already claimed the title of count in 1126, it was not officially recognised as such until 1159. In 1255 the county split into two lines: Nassau-Weilburg and Nassau-Dillenburg. These parts would partition themselves many times in history until the Napoleonic Wars created the Duchy of Nassau (1806-1866) out of Nassau-Weilburg and moved the other parts into the Grand Duchy of Berg (1806-1813). After the Napoleonic Wars the latter became a Prussian province.
The Duchy of Nassau was located close to Frankfurt, the Hessian states and Prussia's western provinces.
Nassau-Weilburg
The Weilburg line produced partitions in Saarbrücken, Idstein, Wiesbaden, Ottweiler and Usingen. From 1728 these were reunited in Nassau-Weilburg and Nassau-Usingen only, and in turn formed the Duchy of Nassau in 1806. Because Nassau sided with Austria in the Austro-Prussian War in 1866 Prussia occupied and annexed the duchy. Its last duke Adolf eventually became Grand Duke of Luxembourg in 1890 after the King William III of the Netherlands (from the Nassau-Dietz line which branched from Dillenburg) died without a male heir. The Nassau-Weilburg dynasty still live on as grand dukes in Luxembourg today.
Nassau-Dillenburg
The Nassau-Dillenburg line inherited estates in the Duchy of Brabant in 1504 when the Low Countries were nominally still part of the Holy Roman Empire. In 1544 the young Prince William acquired the title Prince of Orange, a small principality in what is now southern France, and founded the House of Orange-Nassau which has been the royal house of the Netherlands since 1813. The direct line of William of Orange died out with the death of King William III of England, but lives on through the Nassau-Dietz line.
William left the German county of Nassau-Dillenburg to his younger brother. The county was partitoned a number of times from as early as 1303 producing Nassau-Hadamar and Nassau-Siegen, with the latter becoming Nassau-Beilstein. After some reunifications Nassau-Dillenburg was partitioned again in 1606 into new Hadamar, Siegen, Beilstein and Dietz lines. By 1739 they were all inherited by the Dietz line as the longest surviving branch. In 1806 Nassau-Dietz was united in the Grand Duchy of Berg, a French client state. It became part of Prussia in 1813.
Currency
From 1386 Nassau was part of the Rhenish Monetary Union, which was based on the Goldgulden, a German gold coin which originated from the Florentine Fiorino d'Oro (and in turn the Venetian Ducat). The Goldgulden was divided in 20 Albus (literally White, comparable to the Lübeck Witten or French Blanc) each of 12 Heller. From 1432 this had changed to 24 Albus, each of 8 Pfennig or 12 Heller. Over time the Goldgulden was debased until it became a large silver coin also known as Guldengroschen or Guldiner. In the 16th century the Thaler gained acceptance, initially worth 6/5 Gulden but by the 17th century 1½ Gulden.
The Conventionsthaler was introduced in 1753 and was set at 1/10 of a Cologne Mark (233.86g) of pure silver and worth 1⅓ regular Thaler in Hesse-Kassel. Consequently a Gulden was worth ½ Conventionsthaler or 20 Gulden to the Cologne Mark. In effect a debased version of a 24 Gulden standard gained acceptance in Southern Germany including Nassau. The Gulden was divided in 60 Kreuzer each of 8 Heller.
In 1828 Nassau joined a customs and monetary union based on the Prussian Thaler which was on a 14 Thaler standard. To ease conversion the Gulden was slightly devalued to 24½ per Cologne Mark so that 4 Thaler was equal to 7 Gulden. Nassau issued coins in line with other South German States denominated in Gulden, Kreuzer and Heller. Nassau coinage ceased when it was annexed by Prussia in 1866.
Catalogue
Duchy of Nassau (1806-1866)
https://en.numista.com/catalogue/nassau_duchy-1.html
County of Nassau-Weilburg (1233-1806)
https://en.numista.com/catalogue/nassau_weilburg_duchy-1.html
