Photo manipulation didn’t start with Photoshop! Several famous historical photos were actually manually altered.
For example, this image of General Ulysses S. Grant from the mid-1800s was actually constructed from three source images taken in very different places at different times. General Grant’s head was taken from one image, the body and horse from a different person in another image, and the background from an entirely different scene. Section 3.3 of the book addresses automatic ways to solve this problem.
This image of William Lyon Mackenzie with Queen Elizabeth from 1939 is an early example of manually inpainting a large hole with complex texture. King George VI was fully removed from the picture! Section 3.4 of the book addresses automatic ways to solve this problem.
These examples came from this slideshow at the New York Daily News.