The gray wolf was listed as endangered in the contiguous United States in 1974. On January 4 of that year, the Northern Rocky Mountain gray wolf and eastern timber wolf were listed under the modern Endangered Species Act of 1973. These listings followed earlier protections for wolf populations under predecessor conservation laws in 1967 and 1973.
The 1974 date is sometimes confused with 1978. In 1978, the U.S. Fish and Wildlife Service reorganized the listings and classified the gray wolf at the species level as endangered throughout the contiguous 48 states and Mexico, except for Minnesota, where the population was classified as threatened. Thus, 1974 refers to the initial modern-ESA listings, while 1978 refers to the broader species-level classification.
The listing followed decades of predator-control campaigns, hunting, trapping, poisoning, and the loss of prey. Wolves had disappeared from most of the lower 48 states, surviving mainly in parts of the Great Lakes region. Federal protection helped enable later recovery, including the landmark reintroduction of wolves to Yellowstone and central Idaho in 1995 and 1996.