Yellowstone National Park was established by Congress on March 1, 1872, as the world’s first national park.

The core historical claim is supported. Congress passed the Yellowstone National Park Protection Act, and President Ulysses S. Grant signed it on March 1, 1872, reserving the area as a federally protected park. The law made Yellowstone the first national park in the United States.ebsco.comebsco.comYellowstone Becomes the First U.S. National Park | History | Research Startersbritannica.combritannica.comToday in History March 1 | Yellowstone National Park Established+2 more

Yellowstone is also widely described as the world’s first national park. Britannica and other historical references use that characterization, but the wording is not entirely uncontested. USA Today noted that some historians and reference sources identify Mongolia’s Bogd Khan Mountain as potentially predating Yellowstone, possibly by nearly a century, although its status and date are debated.usatoday.comusatoday.comYellowstone became the 'world's first national park' 151 years ago: See bygone... Because the date and congressional establishment are accurate, and Yellowstone remains the standard historical answer to the first-national-park question, the statement is substantially correct. The material qualification is that “world’s first” should be presented as widely accepted rather than beyond dispute.yellowstone.orgyellowstone.orgYellowstone National Park Facts+2 more