Following on from colour WW2 photos posted last year (link), there are some WW1 ones here - http://nmvsite.com/colour-wwi-photos
		
		
	
	
		 
	
	
		
			
		
		
	
				
			 
	 
	Guy second in on the right has either been photoshopped in for a laugh or looks really out of place!

Although rudimentary colour photography did exist prior to the war, it's safe to say that these have been touched up into colour.
I believe that it is a combination of artist, computer and patience needed to colour photos and film. Happy to be corrected if I'm wrong.
Although color photography was around prior to 1903, the Lumière brothers Auguste and Louis, patented the process in 1903 and developed the first color film in 1907. The French army was the primary source of color photos during the course of World War One.
 
	