Marjory Stoneman Douglas was an early defender of the Everglades but getting everyone else to agree with her and her associates, along with securing federal funding, was tough. According to a 1983 interview with Douglas hosted at the Everglades Digital Library, it all began with a man named Ernest Coe. He teamed up with Douglas' father to create a committee to establish the park and Douglas eventually joined the committee. The group occasionally took scientists, government officials, and other parties to the Everglades, including at least one trip in a dirigible, all in an effort to convince them of the area's need for protection.
One of those people was Arno Cammerer, who would eventually become head of the National Park system. The group, seemingly pretty impressed with the natural environment of the Everglades and, at least in Douglas' recollection, the massive numbers of birds that lived there, "unanimously decided that it must be a great National Park."
The national park was first authorized in 1934 but wasn't actually established until 1947 because of issues getting the land needed for the park, Britannica says. Even then, getting people to support the effort was difficult. Per Biography, Douglas admitted that environmentalism was little more than an odd word back then. "There was no organized environmental movement until the late 1960s, and little understanding of what ecology is about," she said.
