Longtime investor and board member Peter Thiel plans not to seek reelection to Facebook’s board this year, the company announced Monday, ending his tenure as one of the company’s longest-serving board members at a moment of tumult for the social media giant.

Thiel, a right-leaning billionaire and Trump supporter who has also been a close adviser to CEO Mark Zuckerberg, plans to focus his energies on the 2022 midterm elections, according to a person familiar with his thinking who spoke on the condition of anonymity to discuss sensitive matters. Thiel is supporting two close associates, J.D. Vance and Blake Masters, who are running for Senate seats in Ohio and Arizona, respectively. Thiel sees the midterms as a critical moment for the country, the person said, and he is backing a slate of candidates who are allies of former president Donald Trump.

“Peter has been a valuable member of our board and I’m deeply grateful for everything he has done for our company — from believing in us when few others would, to teaching me so many lessons about business, economics, and the world,” Zuckerberg said in a news release.

Thiel, who joined Facebook parent company Meta’s board in April 2005, said in the release: “It has been a privilege to work with one of the great entrepreneurs of our time. Mark Zuckerberg’s intelligence, energy, and conscientiousness are tremendous. His talents will serve Meta well as he leads the company into a new era.”

Thiel will depart Facebook with the company at a crossroads and mired in crisis once again. It is being targeted by governments all over the world for amplifying misinformation and hate, and is facing a major antitrust case in the United States. It shut down a once-touted cryptocurrency project last month in the face of political resistance, and its stock has plummeted as a result of lower-revenue forecasts and a first-ever decline in user growth. Numerous senior executives left the company in 2021.

Last year the company changed its name to Meta in an attempt to refocus itself on virtual and augmented reality and gaming hardware. That new direction is going to be an uphill climb for the company, which has invested more than $10 billion in hiring talent and building out the division Facebook Reality Labs last year, according to its latest earnings reports.

Thiel’s departure, which probably won’t take place until May, leaves the job of overseeing Facebook through this period to the remaining board members, including venture capitalist Marc Andreessen and Drew Houston, co-founder and CEO of Dropbox and a longtime friend of Zuckerberg.

But Facebook’s board has less power than other boards because Zuckerberg controls a majority of voting shares, giving him singular control over his company.

Thiel, a venture capitalist who co-founded PayPal and Palantir Technologies, has long been controversial for Facebook. He joined the board one year after the company was founded, and was one of the first investors to bet big on Zuckerberg’s nascent social media start-up.

In the run-up to the 2016 election, Thiel became more involved in politics and became a vocal supporter of Trump. He helped the company make connections to leading conservative figures and manage a controversy over the alleged suppression of conservative publications. Facebook’s liberal employee base often criticized Zuckerberg’s relationship with Thiel and questioned his influence over the company’s direction, particularly Zuckerberg’s stances on free speech. Thiel has long been a libertarian-leaning conservative who has reportedly influenced Zuckerberg to take more hands-off positions on whether to police misinformation and other harmful content.

Masters is the chief operating officer of Thiel Capital and the president of the Thiel Foundation. Vance is author of the best-selling memoir “Hillbilly Elegy” who previously worked at Thiel’s Mithril Capital Management. Thiel recently backed his Midwest-focused venture fund, Narya Capital, based in Cincinnati.

Thiel has given $10 million to Protect Ohio Values, a super PAC supporting Vance, joining hedge fund investor Robert Mercer and his daughter Rebekah, who have given an additional $150,000 to the effort, according to federal records.

But heavy spending on ads attacking Vance, including from the conservative Club for Growth, has prevented Vance from taking a clear advantage so far in the race, which includes at least three other serious contenders. In fact, a January poll of the race by Vance’s super PAC, which was recently obtained by Politico, found that Vance’s numbers had deteriorated at the end of 2021, putting him in need of a “course correction ASAP that will resolidify him as a true conservative.” The primary is May 3.

Thiel also gave $10 million to a super PAC, Saving Arizona, supporting his former adviser Masters, who is competing for the Aug. 2 Arizona primary. But after that group spent $2.4 million last year to introduce Masters and attack his better-known rival, state Attorney General Mark Brnovich, there is little public evidence that Masters is moving to pull ahead of Brnovich.

In both states, Republican candidates have been courting a Trump endorsement, which could shift the dynamics of the primary contests, but the former president has yet to pick favorites. Trump advisers have said Trump is likely to wait until a candidate emerges from public support in both states, though that plan could change. Trump is known to make decisions on endorsements suddenly, with little warning to those around him.

In the meantime, Thiel has tried to lend his star power and social appeal to Vance and Masters, allowing their campaigns to raise money off opportunities to dine with the billionaire investor.

“Want to have dinner with me and Peter Thiel?” Masters tweeted in August. “Donate $5,800 to my campaign by the end of tomorrow.” For those with less money to donate, Masters offered to spend 20 minutes on the phone with people who sent him $500.

When Trump won the election in 2016, Thiel and Masters helped the Trump transition team scout Silicon Valley for potential hires for the incoming administration, The Washington Post reported at the time.

Thiel moved to Miami last year, part of a wave of notable conservative figures in Silicon Valley making Florida their new home. He has embraced cryptocurrencies and non-fungible tokens, known as NFTS.

Last month Masters tweeted that he and Thiel would mint 99 NFTs of their book, “Zero to One,” and would sell them for contributions to Masters’s Senate campaign. The purchase would also come with “exclusive access to parties with me and Peter.”

Thiel and Vance have backed Rumble, a short-video start-up that aims to become a right-wing competitor for YouTube, Facebook, and TikTok. Rumble also partnered with Trump Media and Technology Group, Trump’s newly formed social media company that aims to take on Big Tech.

Thiel also took on big fights with the media industry, famously financing numerous lawsuits against Gawker Media. The media company ultimately filed for bankruptcy.