During the Middle Ages and the time of the minnesingers green was the colour of love. In the novel "Astrée" written by Honoré d'Urfé, on about 5500 pages, the hero Celadon who sings about his love is dressed in green. Several songs of that time are about the green colour of love.
But not only the colour of love, green was as well the colour of viscous snakes and demons. In the ancient China the dragon still had a positive meaning. It was a symbol for the divine power of transformation, the rhythm of nature, as well as magic wisdom and power. Thus the dragon often was associated to the green colour.
Christianity then changed the meaning of it into a symbol for the bad and the destructive. Christian demons had green skin and green eyes and produced deadly poison and infernal stink.
Fertility as symbol for the colour of love turned into a disreputable thing, as the church wanted to avoid any suspicion on free sexuality. The devil - as a hunter for souls - appeared in a green suit. Although several artists of the Middle Ages painted the Crucifix in green, or saints dressed in green -as a sign for hope - the imagination of green, together with yellow - associated with poison exists still today.
An additional increase of negative meaning arose by the production of "Schweinfurter Green" in the year 1800. This colour was gained from extremely poisonous pigments. When using the colour for painting poisonous vapours developed. This fact was a disaster for Napoleon. Because green was his favourite colour and the rooms in his exile in St. Helena were painted green. When French chemists analysed the dead body of Napoleon they found big quantities of arsenic in his hair and fingernails. The French emperor had not been poisoned as thought before, but he died from a creeping poisoning.
In Christianity the meaning of the colour as a symbol for hope and for renewing still goes on. The Passion week starts with a "Green Sunday", the Lent ends with the "Green Thursday". According to an old custom on this last day of the Lent you eat vegetables or spinach as a symbol for exemption of sins. Green is as well the colour of the normal Sundays, the altars of the catholic churches are decorated with a green cover then. While old paintings often showed Jesus Christ dressed in red (for example "The Resurrection of Jesus Christ", by Matthias Grünewald) and Holy Mary dressed in blue the Holy Spirit often appeared as a white dove in front of a green background. (Thomas Seilnacht)