DW: You've written extensively on flags and national symbols. What are the origins of national flags?
Peter Diem: The flag is an ancient symbol, mainly related to war. From the beginning, they were used to symbolize different armies – early examples could be seen in China, Persia and the Bible. It wasn't until later, when ships began using flags, that these national banners began standing for peaceful communities and nations.
Are there different types of flags?
A standard is carried. It's a piece of cloth attached to a pole, and is never replaced. When it's worn out, it goes to a museum or is burned. A flag, on the other hand, is hoisted on a flagpole with a rope and flutters in the wind. It's something that is used on a daily basis, which means it can easily be replaced by a new flag.
What is the world's oldest surviving flag?
The oldest flag which still exists is from Persia, and dates to the third millennium before Christ. It originated in the East Persian town of Khabis, and features two lions and the sun.
The lion and sun were Iran's state symbols until 1979, when the Islamic Republic introduced a new coat of arms consisting of four crescents and a sword.
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What about a flag's colors? Is there a common meaning for each color, or is it interpreted differently in each country?
This is a question of tradition. The older the flags are, the fewer colors they have. The red-and-white bands of the Austrian flag, for example, date back to 1230. The red-and-white cross on the Danish flag is even older. As more nations were created, more colors were necessary.
But not all colors are used. Usually, a flag consists of one or more of the so-called basic colors – yellow or gold, red and blue – paired with black and white. Green came later, and today is often used in Muslim regions to symbolize the Prophet Muhammad.
And the meaning behind the colors?
Color symbolism is a science in its own right. But it is certainly correct to point out that red often relates to blood, blue with sky and sea, green with forests and meadows, black with death and white with innocence. These are ancient symbols. Red is an especially evocative color and, of course, a symbol of revolution and love.
When it comes to younger countries, who is actually designing the flags?
Usually, it's the result of a design bid, or a competition. If a new nation is looking for a flag, then it has to look at all the existing flags to avoid duplicating a color combination. Then it's probably up to advertising professionals, graphic designers and historians to come up with the new national symbol.
In contrast to most nations, Austria and Germany distinguish between the national flag and the state flag. This dates from a very authoritarian past, when the state authorities had an empire and expressed its power with the coat of arms.
Personally, I believe that this idea has been surpassed with democracy. But nevertheless, it's a fact that there are today two flags in Germany and Austria: the state flag with the coat of arms in the center, and the national flag.
These are also countries which have had a somewhat difficult relationship with the flag.
If used in an ultranationalist manner, the flag can become an undemocratic symbol. Due to the overwhelming propagandistic use and abuse of the flag during the Nazi era, today there remains a certain reserve in Germany and Austria when it comes to displaying the flag.
It's quite different, for example, in the US. People often experience a strong emotional bond when flags are displayed, and so they should be used with caution.
Peter Diem is a media scholar and co-editor of the Austria Forum, an information portal on Austria. He is the author of the book "Die Symbole Österreichs. Zeit und Geschichte in Zeichen" (The Symbols of Austria. Time and History in Signs).