The White House in Washington, D.C. was not always white.
Back when it was called the “Presidential Palace,” it was made of brownstone.
However, in 1814 the British captured Washington, D.C., and burned many government buildings, including the Palace and the Capitol.
So much of its shell was charred from fire that painting the building became necessary.
White covered the burn marks well and brightened the place up.
It had never looked much like a palace anyway, and even less so with bright white paint, so people stopped calling it the Palace and started calling it “the white house.”
Teddy Roosevelt made the popular name official when he had “Theodore Roosevelt, The White House” printed on his presidential stationery.