In the 1950s and 60s, as environmental concerns grew in the United States, there was increasing recognition that the National Park and National Forest systems were inadequate to safeguard wilderness areas from commercial interests. Conservationists, alarmed by the encroachment on these natural spaces, lobbied Congress for more robust protections. This movement culminated in the signing of the Wilderness Act into law by President Lyndon B. Johnson on this date in 1964.