The Enumclaw Plateau, on which the city resides, was formed by a volcanic mudflow from Mount Rainier approximately 5,700 years ago. The name Enumclaw is derived from a Salish Native American term that translates as "place of evil spirits", apparently referring to Enumclaw Mountain .

One of the first white settlers in south King County was Allen L. Porter. In 1853, he claimed a 320-acre parcel on the White River about three miles west of the site of Enumclaw. He maintained a troubled relationship with the local Smalkamish tribe for some time, and in 1855 his cabin was burned to the ground. Porter, who had been warned in advance by a friend in the tribe, hid in the woods until they had left. After warning the settlers at Fort Steilacoom, he left the area, moving to Roy. He would never return to Enumclaw.

Enumclaw itself was homesteaded in 1879 by Frank and Mary Stevenson. In 1885, the Northern Pacific Railroad routed their transcontinental mainline through the site, accepting their offer of cleared, level land on which to build a siding. Confident that the area would grow, the Stevensons filed a plat with King County that same year. They built a hotel and gave away lots for a saloon and a general store.

At first the people called the town 'Stevensonville' after the founders, but they soon refused the honor. One resident suggested 'Enumclaw,' which was the name of the strange sawed-off promontory north of town. The name's uniqueness gained favor with the locals.

Enumclaw has resisted the temptation of box stores in an effort to maintain its livable bucolic image. Its downtown is filled with small local shops, restaurants and services. At least five major employers have chosen Enumclaw for their headquarters: Helac Corp, Mutual of Enumclaw, Nor-Pac Seating, Nether Industries, and Hill AeroSystems. Enumclaw has no B & O tax and per auto dealers, a low sales tax rate when compared to neighboring cities. Enumclaw is the northern gateway to Mount Rainier National Park and is the closest city to Washington State's premier ski area,Crystal Mountain. Enumclaw is also the start of the Chinook Scenic Byway. Enumclaw provides Summer and Fall access to Washington's wine country (Yakima) via Chinook Pass.