As best I can tell, the first celebrity to endorse a commercial product was London actress and socialite Lillie Langtry, who became the poster girl for Pears Soap in 1882. Since no one who worked on that campaign is still around, we will have to trust there was an air of authenticity involved; Ms. Langtry actually did use Pears Soap.
To say much has changed in the 140 years since would be a massive understatement, of course, but on the other hand, much has stayed the same when it comes to the art, if you will, of creating a true, authentic celebrity brand partnership.
