Rocky Mountain National Park legislation was signed on January 26, 1915, and the park was dedicated on September 4, 1915.
An NPS education guide for the park places those two dates on the 1915 line of its timeline. The people page shows the dedication photograph: Enos Mills, F. O. Stanley, Ed Taylor, Mary Belle King Sherman, and Governor George Carlson.
Mills is called the father of the park in that guide because he led the campaign. Sherman used the Federated Women's Clubs to build public support and later worked for Grand Canyon and five other parks. The park was not one person's signature. It was a lobby.