In February, as morale at The Washington Post was reaching new lows, two of the newspaper’s most respected alumni decided to intervene, according to several people with knowledge of the decision.

Leonard Downie, the paper’s top editor for 17 years, and Bob Kaiser, who spent more than a half-century at the newspaper, including as managing editor, emailed The Post’s owner, Jeff Bezos, with a simple message: He needed to cut ties with Will Lewis, its embattled chief executive.

“Replacing him is a crucial first step in saving The Washington Post,” the note said, according to a person who saw it.

Mr. Bezos has not responded to the message, according to the person, and there has been no public sign of daylight between him and Mr. Lewis. But the message is the most pronounced sign of a break between Mr. Lewis and the generation who built The Post into a formidable force in American journalism.

When reached for comment, Mr. Downie, who led The Post’s newsroom from 1991 to 2008, and Mr. Kaiser, who retired in 2014, acknowledged that they had sent the message to Mr. Bezos but would not provide any additional details, saying it was a private appeal.

A spokeswoman for The Washington Post declined to comment. A spokesman for Mr. Bezos did not respond to a request for comment.

Weeks before the note was sent to Mr. Bezos, several of The Post’s best-known journalists had announced they were leaving the newspaper for competitors including The Atlantic, The Wall Street Journal and The New York Times. In January, more than 400 journalists sent Mr. Bezos an open letter urging him to meet with the staff, saying they were “deeply alarmed” by recent decisions at the newspaper. No meeting ever happened.

Mr. Lewis, who took over as chief executive at the start of last year, has been under heavy criticism from current and former Post employees for the better part of a year. Many of his moves have been unpopular, including a reorganization that resulted in the exit of The Post’s top editor, Sally Buzbee; the decision to appoint Robert Winnett, a British editor who later withdrew, as her successor; and referred to David Folkenflik, a media reporter who covers The Post, as “an activist.”

But Mr. Bezos’ transformation of The Post under Mr. Lewis has continued apace. Days before the election, Mr. Lewis announced that the newspaper was ending its tradition of endorsing presidential candidates, a move Mr. Bezos later said was “a principled decision.” Last month, Mr. Lewis explained to staff Mr. Bezos’ decision to reorient The Post’s opinion pages, which had for decades emphasized pluralism, to focus on “personal liberties and free markets.” David Shipley, The Post’s opinion editor, resigned as a result of that shift.

Mr. Downie and Mr. Kaiser join a chorus of other former Post leaders to raise alarms about the state of the newspaper. Martin Baron, who helped revitalize the newspaper as its executive editor for eight years before retiring in 2021, said in an article for The Atlantic this month that Mr. Bezos was “no Katharine Graham,” contrasting him with the longtime owner who saw The Post through its coverage of Watergate and the Pentagon Papers.

Bob Woodward and Carl Bernstein, The Post’s famous Watergate reporters, publicly criticized Mr. Bezos’ move last year to block the presidential endorsement. But Mr. Woodward, who has worked for The Post for more than 50 years, has declined to make other comments on the current state of the publication.

“At some point I’ll write something about it,” he told a Times reporter at an event celebrating Ms. Graham this month.