The mountain was originally named Tahoma or "Great Snowy Peak" by the Yakima Indians. Captain George Vancouver renamed it after Admiral Peter Rainier of the British Navy during a scouting expedition on May 7, 1792. This name was hotly contested for over 100 years, because Americans felt it shouldn't be named after a British officer who had never even been to the U.S.
The first ascent is believed to be in 1852, but is undocumented. The first recorded ascent was on August 17, 1870 by General Hazard Stevens and Philemon Van Trump, via the Gibralter Ledges route. James Longmire introduced the climbing party to the Yakima Indian Sluiskin who provided the party with assistance in getting to the base of the mountain. They climbed in 1 day from their camp just below the Gibralter Ledges. Upon reaching the summit, they nearly collapsed due to exhaustion, but managed to find a steam vent to hide in.
On March 2, 1899 president William McKinley authorized the creation of Mount Rainier National Park protecting 235,625 acres, including over 35 square miles of glaciers blanketing the mountain. There are 25 large named glaciers on Mount Rainier, including the enormous Emmons, which flows down the east face.
It is the highest volcano of the Cascade Range and the fifth highest mountain of the continental USA. This is a huge mountain with multiple glaciers and routes of all technical levels. Mount Rainier, the most heavily glaciated peak in the contiguous United States, offers an exciting challenge to the mountaineer. The regularly climbed routes are the Disappointment Cleaver and the Emmons Glacier which are consider class 4 routes. More than 10,000 people a year try to scale this mountain and many expeditions for bigger mountains come to Rainier for their training runs.
The summit of this mountain is unique to mountains. There are actually 3 separately classified summits of this peak, Columbia Crest which is the highest point at 14,411 feet, Point Success at 14,158 feet to the southwest, and Liberty Cap at 14,112 feet to the northwest all separated by a large crater. The most standard routes actually bring you to the crater rim at 14,150 feet. A lot of climbers consider this as the summit, or close enough, but to attain the true summit, it is an hour walk round trip a quarter mile across the crater to Columbia Crest. Here you can find a summit log.
---- A Word on the Height of the Mountain ----
There has been some questions regarding the true height of the mountain recently. In books it is reported as 14,410 and 14,411. There are a couple sources (unofficial) that report as high as 14,414. However, the National Park Service and all other official sources recognize the height as 14,411.05 feet. This is based on a recent survey of the mountain. This is 12.6 inches taller than figured in 1956 (hence the 1 foot discrepancy in many books). Using data from a constellation of satellites and the number-crunching power of modern computers, Bothell surveyor Larry Signani calculated the mountain's height at 14,411.05 feet—just 12.6 inches taller than the official height computed in 1956 by the U.S. Geological Survey, using traditional triangulation methods.
The new measurement is even closer to the 14,411.1 feet logged in 1988 by many of the same people involved in this latest effort. The new measurement was made using Global Positioning System, or GPS, data, which surveyors can now use to pinpoint elevations with unprecedented accuracy. In late August, a team of six surveyors climbed the summit carrying two lightweight GPS receivers, which detect electronic signals from 24 GPS satellites orbiting the earth. Measurements are calculated by timing how long it takes the satellite signals to reach the receiver and by doing a lot of mathematical gyrations.