A prominent federal whistleblower, Daniel Ellsberg, whose "Pentagon Papers" leak of military documents exposed government deception about the Vietnam War and also eventually led to the downfall of a presidency, has died at the age of 92, according to NPR.

President Joe Biden, who also faces the very real prospect of seeing his own presidency potentially undermined and undone by whistleblower revelations, can only hope that his own whistleblowers find less success in attempting to expose federal corruption and deception than Ellsberg ultimately enjoyed.

Dead from pancreatic cancer

NPR reported that according to his family, Ellsberg died at his home in California on Friday at the age of 92 from pancreatic cancer, the diagnosis of which he had first shared publicly in March.

"Daniel was a seeker of truth and a patriotic truth-teller, an antiwar activist, a beloved husband, father, grandfather, and great-grandfather, a dear friend to many, and an inspiration to countless more. He will be dearly missed by all of us," the family said in a statement.

Ellsberg was born in Chicago, Illinois in 1931, grew up in Detroit, Michigan, and graduated from Harvard in 1952, after which he attended Cambridge University for a year in the U.K. He then served for three years in the U.S. Marine Corps as an officer before returning to Harvard to earn a doctorate degree in economics.

He would go on to serve in various roles at the Defense Department and State Department and as an analyst at the Rand Corporation, during which time he spent two years in Vietnam as an observer as part of a massive undertaking to fully document the U.S. involvement in that decades-long conflict.

Leak of "Pentagon Papers" to media led to Supreme Court precedent on press freedoms

According to The New York Times, it was during his time in Vietnam that Ellsberg became deeply disillusioned with the war effort and, upon his return, quietly became an antiwar protester ahead of his fateful decision in 1970 to become a whistleblower and leak the 7,000-page Pentagon study on the Vietnam War to the public.

He initially sought to deliver the materials, which he secretly photocopied over the course of several months, to top members of the U.S. Senate but was rebuffed and eventually reached out to a reporter he knew with The Times and made arrangements for access to the classified military documents.

The Times soon began to publish articles that exposed how the U.S. government knew the Vietnam War was unwinnable but kept that information secret and continued to escalate the conflict, costing an untold number of lives, and other newspapers eventually followed suit after a court-ordered injunction silenced The Times.

That court order led to a lawsuit that ultimately reached the U.S. Supreme Court and achieved a precedent-setting victory that protected the First Amendment rights of the press.

"Pentagon Papers" leak circuitously led to President Nixon's resignation

The Washington Post, which also became involved in publishing the "Pentagon Papers" and the First Amendment lawsuit, reported that Ellsberg's leak had infuriated President Richard Nixon and his administration, which led to Nixon's formation of a covert group of operatives known as the "plumbers" who were tasked with finding and plugging leaks.

That team, which unsuccessfully burglarized the office of Ellsberg's psychiatrist in search of damaging information to discredit him, would later be caught breaking into the Watergate Hotel to spy on the Democratic National Committee, which of course caused the scandal that resulted in Nixon's resignation in disgrace.

Ellsberg had been charged by the Nixon administration with various crimes under the Espionage Act and was facing up to 115 years in prison, but his case was dismissed prior to a jury verdict after the burglary of the psychiatrist's office, as well as the wiretapping of Ellsberg and attempted bribery of the judge with the FBI director job, was publicly revealed mid-trial.

The famed whistleblower would go on to become a prominent antiwar activist and supporter of other leakers and whistleblowers. He is survived by his second wife, Patricia Marx, and three adult children -- the eldest two from his first marriage to Carol Cummings -- along with five grandchildren and one great-granddaughter.