Minnesota Power has its roots in a handful of electricity companies formed to provide power for a young community, the timber industry and mining interests in the late 1800s and early 1900s in northeastern Minnesota. As businesses thrived and the population grew in the mineral-rich and heavily forested area, several utility companies consolidated and then incorporated in 1906 as Duluth Edison Electric Co., the immediate predecessor of Minnesota Power.

In the early 1920s, six major electric utilities and many municipal and privately owned local plants were operating in what is now Minnesota Power’s service territory. By 1923, after acquiring and consolidating many regional utilities, the company became known as Minnesota Power and Light Co.

The stock of Minnesota Power and Light was first listed on the New York Stock Exchange in 1950 under the ticker symbol MPL. When the corporate name was changed to ALLETE, Inc. in 2000, the stock’s ticker symbol became ALE. Minnesota Power remains the largest division of ALLETE.

In the early days, the company relied on the region's rivers to generate hydropower to serve its customers. In fact, the incorporation papers of the Duluth Edison Electric Co., read in part "to improve, develop and use water power for heat, light and power purposes; and to develop, generate and use electric energy and currents for heat, light and power purposes, otherwise than by water power."

Minnesota Power prospered during and after World War II with the expansion of iron ore mining, forestry/paper industries, grain exports and shipbuilding on Lake Superior. Power plants, including Laskin Energy Center, Taconite Harbor Energy Center and Boswell Energy Center, were built during the 1950s through the 1970s to help accommodate an increasing industrial load.

Today, while still producing power at its hydro stations and the Boswell and Taconite Harbor coal-fired plants, Minnesota Power also generates more than 20 percent of its energy from wind and biomass. The 25-megawatt Taconite Ridge Wind Center began operating in 2008, and the four-phase, 500-megawatt Bison Wind Energy Center in North Dakota was completed in 2015. Laskin Energy Center was converted from coal to a natural gas peaking plant in 2015.