Marlene Adler, Cronkite's chief of staff, told news agencies Cronkite died of cerebrovascular disease.
Cronkite pioneered the airwaves as a trusted anchorman, raising CBS Evening News to a ratings rank yet to be reproduced by the network.
But even before he was voted the "most trusted man in America" by a nationwide survey in 1995, Cronkite had traveled the world, covering World War II battles and Nazi war crime trials for The United Press.
"Walter was who I wanted to be when I grew up," said CBS's "Face the Nation" host Bob Schieffer, 72, who began working at CBS News in 1969.
"He set a standard for all of us. He made television news what it became."
Watch a 1968 Cronkite broadcast on the assassination of Martin Luther King, Jr.
Cronkite was born on Nov. 4, 1916 in Saint Joseph, Mo., but grew up in Kansas City and Houston, Texas.
He began his 69-year career in journalism as a campus correspondent for the Houston Post, while attending high school and college in 1935 -- in the midst of the Great Depression.
Cronkite's first broadcast experience, however, was with radio. He worked as a sports announcer for a radio station in Oklahoma City.
But like most everything in the United States at that time, World War II rapidly changed Cronkite's life -- and career.
Cronkite joined The United Press in 1937, covering battles in North Africa and Europe throughout World War II.
As a member of the renowned "Writing 69th," Cronkite flew in a bombing mission over Germany, landed ashore on D-Day and parachuted with the 101st Airborne -- all just to get the story.
Following the war, Cronkite stayed in Europe to cover the Nuremberg trials, an event he described as "awe-inspiring and rather sickening," in a 1997 interview with the magazine Midwest Today.
But his extensive career had only begun with his travails in Europe. Cronkite soon moved to CBS after a stint as Moscow bureau chief for The United Press.
At CBS, he kicked off his first television broadcast on July 15, 1950 by mispronouncing his name.
"I came back and said, 'So this is Walter Clunk -- Walter Cronkite, saying good lu--good night, good night!" he said to CBS News Correspondent Russ Mitchell in an interview held in 2000.
Muddling his name was not, however, a sign of things to come.
Cronkite's first assignment was to cover the political conventions and elections for CBS in 1952. He continued this coverage until he retired.
"The thing I think I can remember with the greatest pleasure was the chance to pioneer the coverage on television of political conventions and elections," Cronkite said in a CBS News article. "At that time it was a real civics lesson. The conventions were not sanitized for television at all."
Cronkite soon won the anchorman position on CBS Evening News. April 16, 1962, Walter Cronkite faced the nation in his first 15-minute broadcast as an anchorman on April 16, 1962.
A little less than a year later, on Sept. 2, 1963, Cronkite debuted television's first 30-minute weeknight news program with a prominent interview with President Kennedy.
He continued to serve as the network's anchorman and managing editor for 19 years.
View an interactive timeline of Cronkite's career from the PBS series "American Masters."
Cronkite's career rapidly catapulted to international prestige.
Cronkite reached a journalism status many have yet to repeat -- paving the way for future anchormen and women to follow. Still today, Swedish news anchors are called Kronkiters and in Holland, Cronkiters.
His signature signoff, "And that's the way it is," became known in households across the United States. And he was nicknamed "Old Iron Pants," for his levelheaded, even-tempered delivery of the daily news.
But despite his reputation as unflappable, Cronkite delivered some of the most exciting, emotion-packed broadcasts of this nation's time.
From Watergate to the assassination of President John F. Kennedy to Neil Armstrong's first steps on the moon to the Vietnam War, Cronkite guided American viewers through its most momentous news.
Many viewers still remember when Cronkite was nearly brought to tears in his coverage of the assassination of President Kennedy.
Choking on his words on Nov. 22, 1963, Walter Cronkite announced to a somber nation, "From Dallas, Texas, the flash -- apparently official -- President Kennedy died at 1 p.m. Central Standard Time, 2 p.m. Eastern Standard Time, some 38 minutes ago."
His coverage also included the controversial Vietnam War. After covering the Jan. 31, 1968, Tet Offensive in Vietnam, a surprise attack by Viet Cong forces on South Vietnam and U.S. forces, Cronkite delivered a now-famous editorial commentary at the end of the evening program on Feb. 27, 1968.
"For it seems now more certain than ever that the bloody experience of Vietnam is to end in a stalemate. This summer's almost certain standoff will either end in real give-and-take negotiations or terrible escalation. But it is increasingly clear to this reporter that the only rational way out then will be to negotiate, not as victors, but as an honorable people who lived up to their pledge to defend democracy and did the best they could," Cronkite said.
Many commentators believe his critique pushed President Lyndon B. Johnson to open negotiations with the Viet Cong forces.
Cronkite, however, dismissed these notions in an interview with Wolf Blitzer of CNN on Oct. 2, 2002.
"After all, at that moment, President Johnson himself was already making the decision to get out of the war, and I just put one more little needle on the haystack, I think."
A year later, on July 20, 1969, Cronkite gave spine-tingling commentary for 27 of the 30 hours it took for Apollo 11 to complete its mission of landing on the moon. As the country watched Neil Armstrong place his feet on the moon, Cronkite summed up everyone's emotions exclaiming, "Man on the moon! Oh, man!"
Cronkite's coverage of the space race stemmed from his belief that space travel was a crucial and significant piece of world history.
That "man, having left his own environment, could go to a distant orb, could go to the moon, was quite clearly a breakthrough that was going to make an immense difference to the future of mankind," Cronkite said in a July 2000 CBS News article.
Cronkite never lost his love for space exploration. Twenty-nine years later, the veteran anchorman returned to television news to provide coverage of 77-year-old John Glenn's final space flight.
Cronkite's CBS Evening News toppled NBC anchor team Chet Huntley and David Brinkley's nightly news program in the ratings in the late 1960s.
During the entire 1970s, CBS Nightly News maintained complete dominance of the airwaves while gaining a reputation for accuracy, depth and credibility.
Cronkite announced his retirement on Feb. 14, 1980, in what became a national event. And on March 6, 1981, Cronkite said his traditional good-bye for the last time.
Cronkite stayed on at CBS News as a special correspondent and a member of the board of directors.
After his retirement, Cronkite hosted several specials for CBS, as well as for Public Broadcast Service. He also began a column for King Features Syndicate.
His influence and prestige as a respected journalist continued for the rest of his life. In one of his last public observations on policy, Cronkite joined activists in protesting the Bush administration's strategy on Iraq.
In 2002, Cronkite signed a letter that questioned the Bush administration's Iraq policy.
"It seems to me ... in a question as important as this one, whether we go to war, for heaven sakes, we should be entitled to some information about just what it is that the administration knows that it has not shared with us," Cronkite said in his October 2002 CNN interview.
Cronkite is survived by two daughters Nancy Elizabeth and Mary Kathleen and son Walter Leland III. His wife Betsy Cronkite died in 2005.
Editor's Note: This story was originally posted on July 17 and updated on July 18.