Why are carrots orange? It is political.

For centuries, almost all carrots were yellow, white or purple. But in the 17th century, most of those crunchy vegetables turned orange. Why? Turns out it all has to do with Dutch politics. Next Nature explains:

In the 17th century, Dutch growers cultivated orange carrots as a tribute to William of Orange - who led the the struggle for Dutch independence - and the color stuck. A thousand years of yellow, white and purple carrot history was wiped out in a generation.

Although some scholars doubt if orange carrots even existed prior to the 16th century, they now form the basis of most commercial cultivators around the world. Presumably crosses between Eastern (purple), Western (white, red) and perhaps wild carrots led to the formation of the orange rooted carrot sub species....
Whatever the origins, the Long Orange Dutch carrot, first described in writing in 1721, is the forebear of the orange Horn carrot varieties so abundant nowadays. The Horn Carrot derives from the Netherlands town of Hoorn in the neighborhood of which it was presumably bred. All our modern, western carrots ultimately descend from these varieties. {Via}