The website also notes, "The colours address our vital consciousness directly, because they tell of optimism, hope and delight in life", says Monsignor Klaus Mayer, who imparts Chagall's work in mediations and books. He corresponded with Chagall during 1973, and succeeded in persuading the "master of colour and the biblical message" to create a sign for Jewish-Christian attachment and international understanding. Centuries earlier Mainz had been "the capital of European Jewry", and contained the largest Jewish community in Europe, notes historian John Man. In 1978, at the age of 91, Chagall created the first window and eight more followed. Chagall's collaborator Charles Marq complemented Chagall's work by adding several stained glass windows using the typical colours of Chagall.