National uniform color was simply tradition. At a distance, an army’s colors proved incomprehensible save for the Austrians who wore white and the British who wore red. At cannon shot, Prussian blue was much like French blue, and the Russian green was not distinguishable from either of them. Cavalry regiments were particularly difficult to distinguish at longer range, and friendly fire was a constant threat from enthusiastic gunners. —Roman Jarymowycz, Cavalry from Hoof to Track
I came across Cohen's essay while trying to satisfy my curiosity about the origins of the pigment and its relationship to the Prussian military uniform color.
|Vinkhuijzen Collection of Military Costume Illustration, New York Public Library.|
|Fading and Colour Change of Prussian Blue: Methods of Manufacture and the Influence of Extenders,National Gallery Technical Bulletin, 2004|
|The first known painting using Prussian Blue was by Pieter or Adriaen van der Werff: Detail of Entombment of Christ (Picture Gallery, Sanssouci, Inv. No. GK I 10008)|
|Coat of the First Battallion Guard with embroidered Order of the Black Eagle, worn by Frederich the Great. From the collection of the DEUTSCHES HISTORISCHES MUSEUM.|
When Indigo became available from the east, its use was banned in many European countries to protect to the Woad industry. Eventually, however, Indigo, which was defamed as the Devil's Dye, would be adopted throughout Europe and the U.S. because of its superior blue color.
As Cohen points out, Prussian Blue was one of the original 48 Crayola colors, but was re-named "Midnight Blue" in 1958 because students in the U.S. could no longer relate to the history of Prussia. Perhaps teachers grew tired of trying to explain it, or maybe they just didn't know. It seems a shame, because Prussian Blue is a proper name for the pigment. Especially when you consider that in 1958 Crayola introduced two additional pigment-based colors with obscure names: Burnt Sienna and Raw Umber.