Color photography did not really become widespread until the late 30's when Kodak started producing Kodachrome and Kodacolor and Agfacolor from Agfa. There had been color photos however since the Lumière brothers patented the Autochrome process in 1903. I have always loved the almost mystical quality of Autochromes and have in fact tried to duplicate the appearance without much success. There are many Autochromes still in existence including a wonderful collection of photos from World War One which can be found here.
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