The deal, announced Monday, concludes a years-long effort by Paramount to sell Simon & Schuster. An attempted merger with Penguin Random House, the largest publisher in the United States, fell apart after being blocked by a federal judge in October.

“With KKR’s support, we look forward to collaborating on new strategies that will enhance our ability to provide readers a great array of books and to give authors the best possible publication they can receive,” Simon & Schuster’s president and chief executive, Jonathan Karp, said in a statement.

Paramount, then known as ViacomCBS, originally put Simon & Schuster up for sale in March 2020, citing a desire to focus on its core business of video and streaming entertainment. That fall, it struck a nearly $2.2 billion deal with German media giant Bertelsmann, the owner of Penguin Random House. The move would have shaken up an industry already reshaped by consolidation over the past decade, shrinking the ranks of the “Big Five” major publishing houses.

The Justice Department sued in late 2021, saying that the deal would give Penguin Random House, already the largest publisher in the country, almost half of the market for rights to anticipated bestsellers — and therefore “outsized influence” over authors’ compensation and which titles were published. Penguin Random House argued that the deal would promote competition by giving Simon & Schuster access to its sales teams and distribution networks, which would allow all their imprints to pay authors more; other publishers would then be spurred to improve their terms. As the trial unfolded, star witnesses included King (who identified himself as a “freelance writer” and testified for the government) and the literary agent Andrew Wylie, among others.

In a ruling that marked a shift from past policy for similar mergers, Judge Florence Y. Pan sided with the government, one in a string of antitrust victories for the Biden administration that fall. Paramount ended the deal, leaving Penguin Random House to pay them a $200 million termination fee. The search for a buyer resumed not long afterward, with some observers suggesting that if the court decision scared off other major American publishers, private equity would be a probable contender.

On Monday, the Authors Guild, which had called Pan’s ruling “a major victory for authors” and said it would oppose any mergers within the Big Five, said in a statement from President Maya Shanbhag Lang that it “hopes that KKR as a private equity firm will defer to the editorial leadership at S&S, recognizing that publishing is a unique business model that requires vision and creativity in ways that don’t always justify themselves on P&L sheets.”

“In the short term, this will mean recognizing that S&S is a lean company that cannot afford to lose employees or have editorial decisions and processes undermined,” Lang wrote. “In the long term, this will mean recognizing the tremendous value and prestige offered by S&S as a cultural institution and a necessary player in the publishing landscape.”

Simon & Schuster reported a record $1.1 billion in revenue in 2022, according to Publishers Weekly, and sales rose 19 percent in the first quarter of 2023. That growth was primarily driven by fiction, Karp said in May, led by authors including Hannah Grace and Taylor Jenkins Reid, among others.

KKR — which also owns OverDrive, operator of the reading app Libby and the largest distributor of e-books, audiobooks and other digital materials to libraries — said in a statement that it plans to create an equity ownership system “to provide all of the company’s more than 1,600 employees the opportunity to participate in the benefits of ownership after the transaction closes.”