The gray wolf, Canis lupus, was native to the Yellowstone National Park area until a conservation effort in regards to other area wildlife killed off many of the wolves. This conservation effort, better known as "predator control", focused against the gray wolf occurred in the late 1800's and early 1900's. By the 1970's there were no wolves found in the park showing evidence that the predator control efforts had succeeded.

Planning for the reintroduction of the gray wolf began in the 1980's. It was not until 1995 that fourteen wolves were introduced and in 1996 seventeen were introduced. Thus far, the reintroduction process has seemed rather successful.