This recently resurfaced instructional photography book from 1909 shows how retouching was already a thing before Instagram
According to the 1909 edition of the book, “in delivering finished work to your customers, you do not hand them the photographic negatives, but the prints made from these negatives.” It explained that in “the early days of photography prints were made directly from the negative without any alteration.”
The photographers used knives or pencils to etch and retouch negatives so that they made “thick necks made thin, excessive drapery removed, crooked noses straightened, hair added, backgrounds altered,” the book said
And here are some examples made before and after retouching shared in the book
