Here’s an interesting article from a 1912 Geyer’s Stationer publication talking about postcards as a means of attracting new people and new business to an area, with thousands of cards sent out by individuals, and City Chamber of Commerce. Mentioned specifically is Iowa Falls, Iowa’s success; Oskaloosa, Kansas’ plan; and Fresno, California’s campaign with help from the Santa Fe Railroad, that is believed to have brought in many new settlers to the San Joaquin Valley.

Source:  Geyer’s Stationer. May 9, 1912, Vol. 53, no. 1331. p. 34. (Google eBook).