Blue is loved by everyone: it does not want to be noticed and at first glance seems like a humble color. It accompanies, supports, it is the color of the sea and the sky. It is so ubiquitous that sometimes we no longer even notice it, but at the same time it has become a central and symbolic color. There was a historical moment in antiquity when it was little appreciated: only the Egyptians loved it, considering it a good luck charm for the afterlife. It is only much later that blue manages to assert itself: today jeans and shirts are blue, it is the color of the European flag, the UN and UNESCO.
Perhaps the reason for its initial lack of success is precisely due to the difficulty of producing the pigment. The Egyptians used a copper-based technique that we have lost today, while lapis lazuli and azurite were stones that were difficult to find. For the Romans, often, blue had a negative connotation: women with blue eyes were considered loose, it was the color of the "barbarians" and, when the Romance languages sought an accurate terminology to define it, they had to draw from foreign languages: from Germanic "blau" and from Arabic "azraq". Even in the first Christian era, in the time of the Carolingians, liturgical colors excluded blue.
Everything changes between the 12th and 13th centuries thanks to a change in mentality within the Catholic religion. In the Cathedral of Saint-Denis, Abbot Suger has stained glass windows made with cobalt blue and from there the trend expands. Furthermore, precisely from the 12th century, with the birth of heraldry and the need to "catalog" people, one can no longer be satisfied with only red, black and white: green, yellow and blue thus come into play. At the same time, the main promoter of this color becomes the Virgin Mary, the "Queen of Heaven" draped in a blue mantle that alludes to the kingdom of heaven. Since the Virgin dresses in blue, soon the kings of France also begin to do so, imitated by the aristocracy. This stimulates dyers to look for new techniques, leading to important economic consequences. Think that the land of Cockaigne is a metaphor that was born in that era, when in France with woad the coques, blue balls, are produced. In fact, the woad merchants were so rich that they paid approximately 80% of the construction of the Cathedral of Amiens.
The painters' palette is once again disrupted by the split between the Catholic and Protestant Church. Reformed painters often prefer a more sober range and neutral tones: just compare Rembrandt, Calvinist, with Rubens, Catholic, or observe the work of Philippe de Champaigne, whose palette changes along with his faith.
In the 18th century, finally, Prussian blue is discovered, which allows to diversify the dark tones, and indigo begins to be imported. In France, blue becomes the color of the republicans, in opposition to monarchical white.
Pastoureau even goes so far as to define it a "dead cat" color: it does not disturb and is universally accepted by everyone. It surrounds us, it is the color of the flags, of all Western countries, the color of decent people who do not want to expose themselves too much.
