Raleigh County is among the largest of West Virginia’s 55 counties, with an estimated population of 74,591 in 2020, down 5.4 percent since 2010 and a decrease of 22.5 percent from its peak of 96,273 in 1950. Beckley, the county seat, had a population of 17,286 in 2020. In land area, at 608.9 square miles, Raleigh is 10th in the state.

Raleigh County was established on January 23, 1850, by an act of the Virginia General Assembly, with Beckley as its county seat. The county's founder, Alfred Beckley (1802-88), a West Point graduate, named the county after Sir Walter Raleigh, and the town after his father, John James Beckley, first clerk of the U.S. House of Representatives and first Librarian of Congress.

In 1742, John Peter Salling, a German from Orange County, Virginia, led an expedition down the New and Kanawha rivers, noting rich seams of coal along the way. He named Coal River, which has its headwaters in Raleigh County. Dr. Thomas Walker of Albemarle County, Virginia, while searching for lands for the Loyal Company crossed through Raleigh, including the present site of Beckley. He, too, remarked on the coal deposits. Christopher Gist of North Carolina, heading an expedition financed by the London Company, visited the New and Bluestone rivers in 1750-51. By the late 1700s, speculators, including Alfred Beckley's father, were acquiring hundreds of thousands of acres in Raleigh and adjoining counties.

Raleigh's first permanent settler of European descent is not known, but William Richmond, a Revolutionary War veteran, is a good candidate. He acquired a 10-acre tract on New River at Sandstone Falls in 1799. In 1797-98, Francis Farley, an old Indian fighter, was employed by three Greenbrier County (now Monroe) merchants to hack a six-foot bridle path through Raleigh westward 115 miles to present Louisa, Kentucky, on the Big Sandy River. They wanted a path wide enough for the pack animals of trappers from whom they bought large quantities of beaver pelts.

They hoped eventually to widen the path, known as "Farley's Trace," into a wagon road. But a road through Raleigh was not realized until 1810-11, when the Virginia General Assembly, acting on a petition from farmers in Monroe and Giles counties, authorized a primitive state road through Raleigh and Fayette to the Kanawha River as a shortcut to the saltworks at Malden. It was this road that opened the interior of Raleigh to settlement, which followed shortly thereafter. In the 1840s, the Giles, Fayette & Kanawha Turnpike followed the same general route.

Alfred Beckley came to Raleigh after resigning his army commission, hoping to cash in on the 56,679 acres he had inherited from his father. He built his home, Wildwood, at Beckley, settling there with his family in 1837. The county's 1850 population was 1,765.

Since Raleigh was a turnpike crossroads, U.S. and Confederate armies repeatedly traversed the county, as they fought to control Western Virginia during the Civil War. Federal troops occupied the county in early 1862. Col. Rutherford B. Hayes and Sgt. William McKinley were stationed in Beckley for a time during this period. Although no major engagements were fought in Raleigh, skirmishes were frequent. Many homes were burned, and bushwhackers were common. In 1863, Beckley was bombarded by federal artillery.

Mostly Confederate in sentiment, Raleigh supplied two companies of troops to the Southern army. Numerous civilians were arrested by federal authorities and imprisoned at Camp Chase, Ohio, including Alfred Beckley, briefly a Virginia militia general. Others, arrested by the Confederates, were imprisoned at Richmond. Many civilians fled the county. For 35 months, from late autumn 1862 through early autumn 1865, Raleigh suffered a collapse of civil government. County records were sent to Pulaski County, Virginia, for safekeeping.

After the Chesapeake & Ohio (C&O) Railway opened its line through the New River Gorge in 1873, the timber industry flourished, mainly along the mountains bordering the river. The C&O had chosen the north side of the New River, the Fayette County side, meaning a delay in the birth of the Raleigh coal industry, except for the 1891 mine at Royal which was on the river. In 1901, the C&O built a branch line nearly to Beckley, and by 1910 the C&O and Virginian railroads had penetrated every section of the county. Mining boomed. Twenty-one coal companies operated in Raleigh in 1910, producing 2,873,448 tons of coal. The peak year was 1925, when production reached 17,598,224 tons. Nearly a century later, in 2021, that number had dropped to 6,875,818 tons, although Raleigh was still West Virginia’s second leading coal-producing county, trailing only Marshall County.

A banner year came in 1943 during World War II when Raleigh mines produced 16,221,163 tons. From then on, production dropped, falling to a low of 5,191,534 in 1974, then leveling off and rising slightly over the following years. Peak mining employment was 14,226 in 1937, but that fell to 1,803 by 1991. Raleigh's coal production came at a high cost. Between 1897 and 1992, 2,121 Raleigh County workers died as the result of mining accidents. In 1914, 183 miners perished in the Eccles mine explosion, the worst in the county's history and second-worst in West Virginia. County population peaked with the coal industry.

Offsetting the decline in coal has been the development of Raleigh County as a major southern West Virginia trading, government, tourist, and medical center. Mountain State University, formerly Beckley College, was located in Beckley before closing at the end of 2012. The Appalachian Bible College was established at nearby Bradley in 1950 as the Appalachian Bible Institute. The development of the West Virginia Turnpike (I-77) and I-64 has given the county north-south and east-west interstate routes. The four-lane U.S. 19 (Appalachian Corridor L) connects with 1-79 in Braxton County, giving northern travelers a shortcut to the southeast resort states via Beckley. The Beckley to Grundy, Virginia, four-lane Coalfields Expressway is under development.

Notable Raleigh Countians include U.S. Sen. Robert C. Byrd; musicians Little Jimmy Dickens, the Lilly Brothers, and Bill Withers; former Congressman E. H. Hedrick; U.S. Sen. Harley M. Kilgore; Jon McBride, astronaut; Governor Clarence W. Meadows; Congressman Nick Joe Rahall; Chris Sarandon, movie and television actor; former Congressman Joe L. Smith Sr.; Gov. Hulett C. Smith; and John Roscoe Turner, a president of West Virginia University. Raleigh County was especially well represented between 1945 and 1949, with Kilgore in the U.S. Senate, Hedrick in the U.S. House, and Meadows as governor of West Virginia, all at the same time.

Raleigh varies in elevation from 800 feet at Jarrolds Valley in Clear Fork District to 3,560 feet at the summit of Huff Knob on Flat Top Mountain in Shady Spring District. Beckley, at 2,360 feet, averages 55 inches of snowfall annually, exceeding all major cities except Elkins. It is also one of the coolest, with an average temperature of 50.9 degrees, again exceeded only by Elkins at 49.4 degrees. And it is among the wettest at 42.12 inches annually, topped by Elkins and Charleston. The Guyandotte and Coal rivers begin in Raleigh County.

There are three major parks: Grandview, home of two historical dramas and other stage performances, now part of New River Gorge National Park and Preserve; Little Beaver State Park; and Lake Stephens, a county park. Tamarack, an arts and crafts center, opened near the West Virginia Turnpike in 1996.

On April 5, 2010, a series of explosions rocked the Upper Big Branch mine near Montcoal, killing 29. It was West Virginia's deadliest mine disaster since the 1968 Farmington explosion.

In 2023, Raleigh County's largest employers were the county school system, Contura Energy, Raleigh General Hospital, Walmart, and Appalachian Regional Healthcare.