Established by Presidential Proclamation No. 2193 on August 10, 1936 (50 Stat. 1760) as Joshua Tree National Monument. Legislation states that the "lands contain historic and prehistoric structures and have situated thereon various objects of historic and scientific interest…" (50 Stat. 1760). … the legislative history reveals that another major reason for the establishment of the monument was preservation of the natural resources of the Colorado and Mojave Deserts. The natural resource preservation emphasis was so strong that the original name contemplated for the monument was Desert Plants National Park.
In 1984, the monument was set aside as a biosphere reserve by the United Nations Educational, Scientific, and Cultural Organization under its Man and the Biosphere Program.
PL 103-433. 1994. Desert Protection Act. Added 234,000 acres to the unit and changed its status from national monument to national park. Designated an additional 163,000 acres of land as wilderness.