At the end of the 19th Century the rotogravure printing method was developed. This allowed fairly high quality photos to be reproduced, even on news print. Papers that could afford the process printed special sections which contained rotogravure photographs.
These are examples of such pictures taken publiahed WWI are from the Flikr stream War of the Nations, 1919. There are more examples after the jump, and even more at the Flikr stream.