http://whatscookingamerica.net/History/CookieHistory.htm
Peanut Butter Cookies - Hand rolled dough containing peanut butter. Dough is rolled into a ball and then flattened with the tins of a fork.
George Washington Carver (1864-1943), an African-American educator, botanist and scientist from Alabama's Tuskegee Institute, began to promote the peanut as a replacement for the cotton crop which had been destroyed by the boil weevil. By 1903, he developed hundreds of uses for peanuts in recipes. In his 1916 Research Bulletin called How to Grow the Peanut and 105 Ways of Preparing it for Human Consumption, he has a three recipes for peanut cookies calling for crushed/chopped peanuts as an ingredient.
In 1922, Joseph L. Rosefield began selling a number of brands of peanut butter in California. These peanut butters were churned like butter so they were smoother than the gritty peanut butters of the day. He soon received the first patent for a shelf-stable peanut butter which would stay fresh for up to a year because the oil didn't separate from the peanut butter. One of the first companies to adopt this new process was Swift & Company for its E.K. Pond peanut butter - renamed Peter Pan in 1928. In 1932, Rosefield had a dispute with Peter Pan and began producing peanut butter under the Skippy label the following year. Rosefield created the first crunchy style peanut butter two years later by adding chopped peanuts into creamy peanut butter at the end of the manufacturing process.
It is not until the early 1930s that peanut butter was listed as an ingredient in cookies. The 1931 edition of Pillsbury's Balanced Recipes contains a recipe for Peanut Butter Balls.
It instructs the cook to roll the dough into balls and press them down with the tines of a fork. This practice is still common in America today.