Same as for any other flag - to serve as a national symbol.
Norway
Because of Christianity.
Red, blue and white- it looks like London's flag! :)
Saudi
Blue, white and red.
The cross symbolizes Christianity.
Norway
when 1905, why because it be a sovereign nation
Red, white and blue
2 All purpose flags are authorized. -The All-Weather (Storm) Flag -"All-Purpose" Flag
it's obviously Iceland.
The flag is a symbol of the nation. It represents the purpose and resolve of the nation and was first expressed by our Founding Fathers who founded the new nation. The flag represents the history and future of our country. There is an excellent article on Wiki dealing with the flag. You can also read more about the flag at http://www.usflag.org/uscode36.html