Strom Thurmond, a South Carolina Republican who forged one of the most remarkable careers in American public life while becoming the longest-serving U.S. senator in history and the oldest person to serve in Congress, died last night in his home town of Edgefield, S.C. He was 100.

Thurmond's death was announced to his former colleagues at about 11 p.m. by Majority Leader Bill Frist (R-Tenn.), who interrupted Senate debate on a major Medicare bill to salute a man he called "a close friend, a confidante, a colleague." Thurmond had decided not to seek another term last fall and left the Senate in January.

Thurmond died at 9:45 p.m., his son, Strom Jr., said. He had been living in a newly renovated wing of a hospital in Edgefield. Frail and wheelchair-bound in his final years, Thurmond was a robust man for decades, proud of his ability to do dozens of pushups and harsh on aides who pursued unhealthy practices such as smoking cigarettes.

Once an outspoken and intransigent defender of racial segregation, Strom Thurmond burst on to the national scene in 1948 as the presidential nominee of the "Dixiecrat" States' Rights Party. For more than two decades, he fought the civil rights movement that transformed the nation in the last half of the 20th century.

With Harry Dent, a key aide who later worked for President Richard M. Nixon, Thurmond helped devise the "southern strategy" that paved the way for a Republican majority in the South. Its essence was an appeal to white resentment of court-ordered school desegregation and similar developments. But when it became clear that the tide of civil rights could not be turned back, Thurmond embraced a policy of racial inclusion.

Thurmond was a former state legislator, circuit judge and governor. He was a decorated veteran of World War II -- as a 41-year-old Army glider pilot, he landed in Normandy on D-Day. He later was a major general in the Army Reserve.

With his courtly manners and inimitable drawl, he was the personification of a southern gentleman. He also was a teetotaler, a physical fitness buff and an admirer of young and beautiful women. His first wife was his junior by 23 years. His second wife, Nancy Moore, a South Carolina beauty queen, was 44 years younger than he. The two had been separated, but remained married for many years.

Thurmond became a father for the first time at the age of 68, and he became a first-time grandfather last week.

His most important quality was an ability to adapt to political reality. The turning point was the 1970 gubernatorial election in South Carolina, in which his candidate raised the racial issue and lost. In 1971, Thurmond for the first time appointed a black professional to his Senate staff. He also began sponsoring African Americans for federal judgeships and other jobs. He was one of the first southern lawmakers to do so.

Black South Carolinians began receiving an increasing share of the constituent services that Thurmond always had provided to whites. The state's traditionally black colleges were included in federal funding programs. Thurmond attended their football games, and for years he sponsored a Senate resolution to designate a National Historically Black Colleges and Universities Week.

In 1983, he supported legislation that made the birthday of Martin Luther King Jr. a national holiday even as some other southern Republicans -- then-Sen. Jesse Helms (R-N.C.), for example -- bitterly opposed it.

"Times change and people change, and people who can't change don't stay in office long," he told an interviewer. "You got to meet changing conditions."

He had a seemingly unbreakable hold on the loyalty of South Carolina voters. Part of the reason was prosperity. Formerly an agricultural backwater, South Carolina became an economic power in the New South. The Navy virtually abandoned its bases in the state, but shopping malls, industry and retirement communities sprang up everywhere and more than made up the difference. Always a friend of business, Thurmond helped it happen.

With the passage of years, the harsh memories of his earlier career began to fade. Although he never received more than 20 percent of the black vote, his about-face on racial matters made it impossible for challengers to form a political base from which to defeat him.

The passage of years also increased his power. Seniority brought at different times the chairmanship of the Senate Judiciary and Armed Services committees. It made him president pro tem of the Senate, a position that put him in line to succeed the president, after the vice president and speaker of the House of Representatives. As president pro tem, he presided over the opening of the impeachment trial of President Bill Clinton.

Some observers felt that the Armed Services Committee tended to bog down in details under his chairmanship, but a plan to replace him went nowhere. In 1998, he voluntarily relinquished the chairmanship to Sen. John Warner (R-Va.), who took over in the beginning of 1999. In 2001, the increasingly frail senator announced he would not seek reelection.

While Thurmond's final years in the Senate were generally quiet, he indirectly created an uproar upon his retirement. At a Capitol Hill celebration of his 100th birthday in December, Sen. Trent Lott (R-Miss.) -- then the majority leader -- noted that Thurmond had carried Mississippi in his 1948 segregationist presidential campaign. "If the rest of the country had followed our lead," Lott told the audience, "we wouldn't have had all these problems over all these years."

The comment seemed to embrace segregation; it prompted a furor and Lott was unable to save his leadership post. Frist replaced him.

Thurmond was a conservative icon for whom the key issues were national defense, fiscal responsibility, support for the family and strong law enforcement. Over the years, he introduced several bills providing the death penalty for federal crimes and curtailing the power of federal courts to review state criminal cases. He backed Robert H. Bork, the conservative former appeals court judge whose nomination to the U.S. Supreme Court failed, and Clarence Thomas, the Georgia-born African American who became an associate justice of the court.

But he took the liberal view on a number of other matters. In 1978, he voted for a constitutional amendment that would give the District of Columbia full voting representation in Congress. In 1982, while chairman of the Judiciary Committee, he voted for renewal of the Voting Rights Act. The next year, he worked on a successful compromise to preserve the U.S. Civil Rights Commission.

In 1991, in the wake of a Supreme Court decision, he voted for a bill to make it easier to prove discrimination in employment cases. He sponsored ethics legislation and bills to require warning labels on alcohol-based products. He backed the use of fetal tissue in research. One of his daughters had diabetes, and fetal tissue is used in research on the disease.

On other occasions, he co-sponsored a crime bill with Sen. Edward M. Kennedy (D-Mass.) and joined former senator Howard Metzenbaum (D-Ohio) in calling for a ban on plastic guns. He backed other gun control measures endorsed by police associations.

As governor of South Carolina in the late 1940s, he took the lead in abolishing the state's poll tax. He also increased expenditures on education, including education for blacks, and he established a higher minimum wage. He threw all the state's resources behind an effort to bring a lynch mob to justice.

But it was as a segregationist and a defender of "the southern way of life" that Thurmond first gained national prominence. His candidacy under the States' Rights Party in 1948 was in response to a civil rights plank the Democratic Party included in its presidential platform.

President Harry S. Truman, the Democratic nominee, was pilloried for integrating the armed forces. Thurmond described the Democratic civil rights program as "the most un-American law ever proposed. It was borrowed from the communists, who know well that they can never gain control of America as long as our fundamental rights are preserved to the states."

He said he was "not interested one whit in the question of white supremacy," but that southern whites were being forced to entertain blacks "in their living rooms" and "swimming pools."

"All the laws of Washington, and all the bayonets of the Army," he continued, "cannot force the Negro into our homes, our schools, our churches and our places of recreation."

The States' Rights Party carried South Carolina and three other Deep South states.

Elected to the Senate in 1954, Thurmond opposed all of the great civil rights laws of the next two decades. He was a leading critic of the Supreme Court's decision in Brown v. Board of Education, the case in which "separate but equal" public education was declared unconstitutional.

In 1956, he wrote the Southern Manifesto, the blueprint for resistance to Brown. Signed by 19 senators and 81 representatives, it called the decision "a clear abuse of judicial power" that should be resisted "by all lawful means."

He staged the longest one-man filibuster in Senate history, holding the floor for 24 hours and 18 minutes in a futile effort to block housing provisions of the 1957 Civil Rights Act. The measure already had been watered down to the point where other southern legislators were prepared to let it pass.

In 1964, he wrestled Sen. Ralph Yarborough (D-Tex.) to the floor outside the Senate Commerce Committee. The idea was to deny the panel the quorum it needed to act on the nomination of former governor Leroy Collins of Florida to head the Community Relations Service, which had been established to mediate racial disputes.

In the same year, he abandoned the Democratic Party, the party of his father, then joined the Republicans and supported Sen. Barry Goldwater of Arizona, the GOP presidential candidate. Like Thurmond, Goldwater had voted against the landmark 1964 Civil Rights Act.

"The Democratic Party has forsaken the people to become the party of minority groups, power-hungry union leaders, political bosses and big businessmen looking for government contracts and favors," Thurmond declared. "If the American people permit the Democratic Party to return to power, freedom as we have known it in this country is doomed."

South Carolina was one of six states carried by Goldwater.

In 1968, Thurmond helped Nixon win the GOP presidential nomination by holding southern delegates in his camp. In a meeting prior to the convention in Miami Beach, Nixon had gained Thurmond's support with promises of a strong defense policy and efforts to protect the South Carolina textile industry from foreign competition.

The other candidates for the Republican nomination were Gov. Nelson A. Rockefeller of New York and Gov. Ronald Reagan of California. Like many Southerners, Thurmond admired Reagan but thought he could not be elected. He regarded Rockefeller as too liberal.

It was in the 1968 campaign that the "southern strategy" was born. Its message relied on code words and phrases. For example, "freedom of choice," a term used by Thurmond, meant opposition to school desegregation. Similarly, Nixon pledged that he would not make the South a "whipping boy," meaning that his administration would enforce the law, but also would be sympathetic to southern concerns.

When the general election returns were counted, Nixon gained 63 electoral votes in the Deep South on his way to winning the White House, compared with 45 for Gov. George C. Wallace of Alabama, who was a third-party candidate, and 25 for Vice President Hubert H. Humphrey, the Democratic standard bearer.

The late Lee Atwater, the South Carolinian and former Thurmond aide who headed George H.W. Bush's campaign for the presidency in 1988, described the 1968 race as the "blueprint for everything" he did in the South.

By 1970, it was clear that the racial politics were losing their appeal. When Thurmond's candidate for governor lost, Dent convinced him that the time had come to "take the high ground of fairness on the race question." A few weeks later, he hired Thomas Moss, the head of the Voter Education Project in South Carolina, to a key position on his staff.

Thurmond never renounced his segregationist past and denied he had had a change of heart on racial matters.

"I've done everything I could to help the people of both races throughout my lifetime," he said in an interview. On another occasion, he said he could not understand how he had "got such a reputation as a segregationist. I think my position was just misunderstood. I guess it was because when I was the governor of South Carolina, it was my duty to uphold the law, and the law required segregation. So I was just doing my duty."

James Strom Thurmond was born on Dec. 5, 1902, in Edgefield. His parents were John William and Eleanor Gertrude Strom Thurmond. The town had a tradition of radical southern politics. It was the home of Sen. Preston Brooks, who nearly beat an abolitionist opponent to death on the floor of the Senate before the Civil War, and of Chancellor Wardlaw, who wrote South Carolina's Ordinance of Secession in 1861.

Strom Thurmond's grandfather was a veteran of the Mexican War and the Civil War. His father was an ally of "Pitchfork Ben" Tillman, one of the most rabid racists ever to sit in the United States Senate. The father shot a political rival to death, but was acquitted on the grounds of self-defense. Tillman persuaded President Woodrow Wilson to appoint him U.S. attorney for western South Carolina.

The future senator recalled meeting Tillman. "I said, 'I want to shake hands with you.' And he took my hand and he said, 'What do you want to do? Shake hands? Well, why in hell don't you shake, then?'

"I started shaking and I've been shaking hands ever since."

Thurmond graduated from what is now Clemson University in 1923 and became a schoolteacher. In 1930, he passed the South Carolina bar, having studied law under the tutelage of his father. He was elected to the state senate in 1932. In 1938, he was named a circuit judge.

After college, Thurmond went into the Army Reserves. In World War II, he was called to active duty. He was attached to the 82d Airborne Division and landed in France aboard a troop glider on the day of the Normandy invasion. His unit was cut off for two days before it joined up with the main allied forces. Later in the war, Thurmond served in the Pacific.

Thurmond was governor of South Carolina from 1947 to 1951. He was defeated in his first bid for the U.S. Senate in 1950. He practiced law until 1954, when he became the first write-in candidate to run for the Senate successfully. In 1956, he resigned to fulfill a campaign pledge to run in a general election without the advantage of incumbency. He won handily, as he did in every race after that in which he was a candidate.

Thurmond was chairman of the Senate Judiciary Committee from 1981 to 1987 and chairman of the Armed Services Committee from 1993 to 1999.

His military decorations included the Bronze Star with combat "V," the Purple Heart and the French Croix de Guerre. He retired from the Army Reserves in 1960.

On Nov. 7, 1947, he married the former Jean Crouch, and demonstrated his fitness to a Life magazine photographer by standing on his head for a picture the day before the wedding. Jean Crouch Thurmond died in 1960.

On Dec. 22, 1968, Thurmond married Nancy Moore, the former Miss South Carolina.

In addition to Mrs. Thurmond, of Aiken, S.C., survivors include three of their four children: J. Strom Thurmond Jr., Juliana Gertrude Thurmond and Paul Reynolds Thurmond.

A daughter, Nancy Moore Thurmond, was killed in 1993 when she was struck by a drunk driver while crossing a street in Columbia, S.C.

Strom Thurmond was the longest- serving senator.In 1948, then-South Carolina Gov. Strom Thurmond lunched with his wife, Jean, on the eve of the presidential election, in which he carried four Deep South states as the head of the Dixiecrat ticket. Thurmond and Mississippi Gov. Fielding L. Wright, his running mate, with supporters in the 1948 presidential campaign.Announcing a reelection bid in 1984, Thurmond introduced his family as his "secret weapon." From left were his wife, Nancy, and children Juliana, J. Strom Jr., Nancy Moore and Paul Thurmond. Thurmond first became a father at age 68, and last week he became a grandfather for the first time at 100.Thurmond and Republican nominee Barry Goldwater appeared at a rally in Greenville, S.C., during Goldwater's campaign in 1964. Thurmond huddled with Sen. Joseph Biden Jr. on William H. Rehnquist's nomination as chief justice of the Supreme Court.