Mr. Clinton was separately found in contempt of court and fined by a federal judge. In his final hours before leaving office, Mr. Clinton struck a deal with Mr. Starr’s successor in which the president admitted not telling the truth under oath, paid a fine and surrendered his law license.

But Mr. Starr became “the most criticized man in America,” as he himself put it, the target of Clinton allies and the punchline of a thousand late-night comedy sketches. “Half the country loved him. The other half loathed him,” Ken Gormley, the author of a book about the struggle between Starr and Clinton, once said.

There was never any reconciliation between Mr. Starr and the Clintons. During an interview in 2009, Mr. Clinton talked about the various one-time foes he had come to befriend or at least make peace with, including Mr. Bush, Newt Gingrich, Rupert Murdoch and Richard Mellon Scaife. What about Mr. Starr, he was asked. “Well,” Mr. Clinton said, and then paused. “That’s another kettle of fish.”

Indeed, when Mr. Starr re-emerged two years ago to defend Mr. Trump, Mr. Clinton’s allies did not hold back. “Whether it was representing Big Tobacco, obsessing about President Clinton’s sex life or disgracing himself in the Baylor rape scandal, Ken Starr has always been on the wrong side of history, ethics, and common decency,” Paul Begala, a former aide to Mr. Clinton, said at the time.

But Mr. Starr’s friends and admirers always insisted that he was misunderstood by the public and caricatured by the Clinton political machine. For all his notoriety, they saw him as a genial, principled, professional lawyer, who acted not out of animus but out of genuine commitment to what he thought was right.

“Ken was a truly kind and wonderful person,” Elizabeth M. Locke, a lawyer and protégée from Kirkland & Ellis, said on Tuesday. “Contrary to so much that has been written about him and the way he was portrayed in the wake of the Whitewater investigation, he was one of the most gentle souls you would ever know. And he was one of the most ethical lawyers I have ever met.”