Muir and Johnson worked together to create Yosemite National Park in 1890 and to get California to cede its ownership and management of the Mariposa Grove and Yosemite Valley back to the federal government to become part of the Park in 1905.

Johnson wrote to Muir in July 1906

“Sound the loud timbrel o'er Yosemit-ee!

Jehovah hath triumphed: His forests are free!”

“…you and I planned the details of the campaign for a Yosemite National Park, [and] that California would be glad to merge into its protecting environment the long mismanaged valley. This having worked out exactly as planned, I send you my congratulations on the accomplishment of our hearts' desire.”