Champion-International Paper was a large paper manufacturer originally founded in 1937 as U.S. Plywood Corporation. There's a good bet that if you collect ephemera you've got something manufactured by Champion. Perhaps an old movie magazine like say...Modern Screen.
Modern Screen debuted in 1930 as a magazine providing pictorials and interviews with movie stars. Somewhere in this house I know I have an old copy of Modern Screen from the 1960s. The magazine ceased publication in 1985.
But at one point, specifically the April 1955 National Geographic, Champion-International and Modern Screen came together to use Marilyn Monroe. Didn't everybody use Marilyn Monroe? Did she get a piece of the action for this ad? Did her agent work out a deal or were laws so different then on how a celebrity likeness could be used that this was as much as a surprise to her as those who opened National Geographic and saw Marilyn smiling back at them?
Well Champion-International is now International Paper. Modern Screen is no more. And Marilyn? Marilyn is still out there hawking products whether she likes it or not.
Click on image to see it larger. (SOURCE: National Geographic April 1955)