Which U.S. president signed the 1872 law creating Yellowstone National Park?

Ulysses S. Grant signed the 1872 law creating Yellowstone National Park.

The Yellowstone National Park Protection Act became law on March 1, 1872. It set aside a large area around the Yellowstone River and its geothermal wonders as a public park “for the benefit and enjoyment of the people.” Yellowstone was the first national park established by the United States and is widely regarded as the world’s first national park.

The law followed the Hayden Geological Survey of 1871, which documented Yellowstone’s geysers, canyons, lakes, and other features. Photographer William Henry Jackson and artist Thomas Moran helped bring the region’s landscape to national attention. Their images strengthened arguments for preserving the area rather than opening it to private development.

Grant’s signature is sometimes confused with Theodore Roosevelt’s later conservation work. Roosevelt created the modern conservation legacy associated with national parks, but Yellowstone predates his presidency by nearly three decades. The National Park Service itself was not created until 1916, so the U.S. Army initially helped administer Yellowstone.