The Netherlands use orange on his home jersey, and on the official KVVB (Royal Dutch Football Association) online shop, you can find a supporter flags similar to the image below. So, why the orange?
The answer is: this is the color of the House of Orange-Nassau, the royal house of the Kingdom of the Netherlands. Although the Princes of Orange seems to have used the orange fruit as one of their symbols, orange was, curiously, the livery color of the House of Nassau. The original flag of Netherlands was orange-white-blue, but the first was gradually substituted by red along the years.
Several members of the House of Nassau appears on portraits with a orange bend, like this, representing Henry Casimir I of Nassau-Dietz, painted by Wybrand de Geest:
With the foundation of the House of Orange-Nassau, the orange color became a symbol of Dutch royal house. On the royal birthdays, for example, the national flag should fly with a orange pennant above, as a sign of allegiance:
With time, orange was turning from a royal color to a national color, and became a symbol of Dutch pride. Its use was specially remarkable during WW2, when the country was occupied by the Nazi.
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