Long-time readers of this blog will know that I take a mild interest in the developmental history of photography, as mentioned here and here.
I have heard about this photo, but only came across it the other day. It is the oldest surviving colour photograph in the World and was taken as early as 1861 by James Clerk Maxwell. He discovered that colour photography was possible using red, green, and blue filters. However, due to the lack of development and limited use available, colour photography did not really kick off for another forty years with the invention of autochrome. Even then it didn't become widespread until the 1930's and 40's, when photographic film came on the market.