In America there is Orange County, NY, named after Ulster Scots. In Northern Ireland, there's the Orange Order. In England, there was William of Orange.
However, England doesn't grow oranges. What Orange was William of? How did it get its name? Do they actually grow oranges there?
The William of Orange you're probably referring to (there were several) is William III, who, though he became King of England, Scotland, and Ireland, was actually not English but Dutch. He was born in the Hague, Netherlands, in 1650. In 1688, seven English nobles invited the Protestant William, who had previously married England's Princess Mary, to wrest the English throne from her father, the unpopular and Catholic King James II. Marching on London with an army of 15,000 William met with virtually no opposition. The crown thus changed hands without bloodshed in what came to be known as the Glorious Revolution.
The Orange in William's title referred not to the fruit or the color, but to a region of Southeast France that was among William's family holdings. It is likely that the citrus fruit, which was of Chinese or Indochinese origin, inherited its western name from this area, in which it was grown.
—The Fact Monster