Published: March 31, 2011

YORBA LINDA, Calif. — Most presidential libraries are as much celebrations of a president as historical repositories. They are packed with official papers, photographs, limousines, proclamations and baby shoes representing the president’s life and times; dark chapters are traditionally ignored or at least understated.

That tradition was exploded Thursday as the Watergate Gallery opened here at the Richard Nixon Presidential Library and Museum. The unveiling ended a nearly yearlong struggle between national archivists and the Richard Nixon Foundation, a group of Nixon loyalists who controlled the former president’s papers until ceding them to the National Archives four years ago. The fight was over how to portray the scandal that led to Nixon’s resignation.

From the first words a visitor sees entering the gallery — a quotation from Nixon, “This is a conspiracy” — the exhibit offers a searing and often unforgiving account of one of the most painful chapters of the nation’s history. The timeline methodically chronicles the stream of misdeeds leading up to the Watergate break-in, followed by the attempts to cover it up, which led to Nixon’s resignation.

It is a far cry from the library’s original Watergate exhibition, “The Last Campaign,” created by the Nixon Foundation with the former president’s direct involvement. That installment portrayed Watergate as an orchestrated effort by Democrats to overturn the 1972 election.

Timothy Naftali, the director of the library and the curator of the exhibition, said that given the uniqueness of the Nixon presidency — starting with the fact that he was forced out of office — there was no other way to honestly depict the complicated bundle of scandals that have become known as Watergate. He said the conflict with the foundation was unavoidable.

“It was inevitable, wasn’t it?” Mr. Naftali said. “This was a private institution with a particular point of view. It was accustomed to presenting the president in a certain light. I was coming in as a professional historian who was committed to making sure the facts were known.”

Mr. Naftali said he had no interest in prolonging the disagreement with the Nixon Foundation, and declined to discuss negotiations with them.

“I would actually like the healing to start,” he said. “I’m sure they are as tired of this fight as I am.”

The archivist of the United States, David S. Ferriero, flew in for the ribbon-cutting, reflecting the national significance of the project. None of the foundation’s board members attended. The chairman, Ronald H. Walker, posted a statement on the foundation’s Web site that also appeared to take pains to end the battle.

“Nearly 40 years after President Nixon left office, Watergate remains a controversial and much-studied subject,” he said. “It is, however, just one chapter in the enormously consequential life and career of the 37th president of the United States. The new Watergate exhibit at the Nixon Library represents one interpretation of the events that led to President Nixon’s resignation in 1974.”

Sharon Fawcett, the assistant archivist for presidential libraries, said that other presidential libraries were making increased efforts to deal with difficult chapters of a presidency: Iran-contra is reflected in the Ronald Reagan library, and the library for Franklin D. Roosevelt notes his failure to respond to the Holocaust.

This one, though, is, by any measure, far more harsh. The Watergate gallery is the largest one in the museum. In tone and substance, it is nothing like what one finds in presidential libraries devoted to Truman and Hoover, for example.

The sections within the gallery have titles ranging from “Dirty Tricks and Political Espionage” to “Road to Resignation” to “The Coverup.” Panels on the wall invoke famous quotations, like “What did the president know, and when did he know it?” and one from a Time magazine editorial urging Nixon to resign, reading: “Richard Nixon and the nation have passed a tragic point of no return.”

But the Watergate exhibition is particularly evocative because the curators were able to draw on two resources not available to most presidential libraries. For one thing, it draws on some of the 2,700 hours of secret tapes Nixon recorded in the Oval Office. With the push of a button, in a technology that Mr. Naftali likened to an iPad, a visitor can hear Nixon in incriminating conversations with associates in the Oval Office. His words scrawl along in text to help listeners decipher the often scratchy recordings.

For another, the curators drew on 131 oral interviews they did with critical figures in the Nixon presidency and the scandal, in which they reflect on what happened. “We used the oral histories and the tapes to substantiate the claims that we express in these panels,” Mr. Naftali said.

In one, Alexander M. Haig, who served as a Nixon chief of staff, told Mr. Naftali that Nixon had asked him to burn the tapes and that Mr. Haig had refused. At the same time, Mr. Haig has also said that Nixon’s biggest mistake was failing to destroy the tapes. In another, George P. Shultz, who was Treasury secretary under Nixon, said he had refused Nixon’s request to help him gather information for the president’s infamous enemies list.

“I was being asked to do something improper, and I wouldn’t do it,” he said.

At one point, responding to an early version of the exhibition, the foundation filed a 150-page report requesting significant alterations. The foundation said the exhibition failed to point out, for instance, that other presidents had also surreptitiously recorded people in the White House or gone after political enemies.

Almost none of the requests made by the foundation was reflected in the final exhibition.

A steady stream of visitors walked through after the opening, among them George A. Summerhill, 73, a retired paper manufacturer from Reno, Nev.

“It’s devastating,” Mr. Summerhill said as he emerged from the end. “I mean, so many people felt Nixon betrayed his country.”

Mr. Summerhill, who said he voted for Nixon, said the exhibition was fair and belonged in any presentation devoted to Nixon’s life. “I am looking at this and watching it with mixed emotions,” he said. “I have great respect for Richard Nixon. I can look past this.”

A version of this article appeared in print on April 1, 2011, on page A19 of the New York edition.