At its peak, the five mines of Kennecott: Mother Lode, Glacier, Bonanza, Jumbo & Erie, produced $32.4 million in copper ore in 1916. Between 1909 and 1938, Kennecott produced 4.6 million tons of ore and 1.183 billion pounds of copper.

The Kennecott mine and mill town were named after the Kennicott Glacier, which lies in the valley below the mine, although with a slight misspelling. The change is blamed on a clerical error.

The Alaska Syndicate, headed by Daniel Guggenheim and J.P. Morgan, had bought 40% of the Bonanza Mine from the Alaska Copper and Coal Company in 1906. Eventually, the venture turned public, and the Kennecott Copper Corporation was launched in April of 1915.

At its peak, 300 people worked in the mill town, and up to 300 more in the mines. A self-contained company town, Kennecott contained a hospital, general store, school, skating rink, tennis court, recreation hall, and dairy.

The Great Depression had driven down the price of copper, and by 1938, the quality of ore coming out of the mine had dropped. The final train traveled from Kennecott down the CR&NW rail line in November of 1938.

Deserted for decades, Kennecott was designated a National Historic Landmark in 1986, six years after Wrangell-St Elias National Park & Preserve was established. Much of the old mill town was purchased by the National Park Service in 1998. Since then, NPS has been slowly stabilizing and rehabilitating several of the structures within Kennecott.