The Bridger Wilderness was designated as a Primitive Area in 1931, making it one of the first Primitive Areas in the country. This area was expanded in 1937 to cover the southern portion of the Wind River Range. In 1964, with the passage of the Wilderness Act, 392,169 acres were designated as the Bridger Wilderness, making it one of the first Wildernesses in the National Wilderness Preservation System. In 1984, the Wyoming Wilderness Act increased the size of the Bridger Wilderness by 36,000 acres.