As the sun came up in London on June 24, 2016, Arron Banks and Andy Wigmore were walking through Westminster, the political district of London, smoking cigarettes and drinking champagne from the bottle. The shocking result of the referendum on Britain’s membership in the European Union had just been announced: Leave had won.

Banks, an entrepreneur whose fortune comes primarily from owning insurance companies, had financed and directed the most aggressive wing of the Leave campaign, Leave.EU, and he had given or loaned a total of thirteen million dollars to various anti-E.U. causes. In Britain, where campaign-spending laws have historically been stringent, and donations modest by American standards, Banks’s contributions are thought to constitute the largest sum ever donated by an individual to a political campaign. Banks, who is fifty-two, is short and moonfaced, and often talks with a mischievous half smile; Wigmore, a former Conservative Party operative who serves as Banks’s communications chief, also fifty-two, has floppy black hair and a chaotic manner. Virtually inseparable, and prone to boyish humor, they refer to each other as Banksy and Wiggy.

Although the Leave campaign was officially led by Vote Leave, a group whose figureheads included the cabinet ministers Boris Johnson and Michael Gove, Banks believed that Leave’s victory was in many ways his victory. He had given considerable financial support to Nigel Farage, the sharp-tongued Euroskeptic, which had allowed Farage to remain at the center of the Brexit debate. Many experts also believed that the rambunctious Leave.EU campaign—which stoked fears of uncontrolled immigration—had roused voters who had been unmoved by the more technocratic messages of Vote Leave. A typical Leave.EU post on Facebook warned voters that “immigration without assimilation equals invasion.” A post about the dangers of “free movement” within the E.U. was accompanied by a photograph of ticking explosives.

That night, Banks and Wigmore had stood by Farage’s side as he proclaimed victory, at a crowded party on the banks of the Thames. Farage called the referendum “a victory for ordinary people,” adding, “We have fought against the multinationals, we have fought against the big merchant banks, we have fought against big politics, we have fought against lies, corruption, and deceit.” He concluded, “Let June the twenty-third go down in our history as our Independence Day!”

Shortly after 5 a.m., Banks and Wigmore took the champagne and headed for a friend’s apartment, to shower and change before making media appearances. On the way, they spotted an old man, in a tattered Barbour jacket, attempting to withdraw large sums of money from an A.T.M. The old man recognized them. He was terrified that the vote would cause a run on banks in the United Kingdom, and told them, in a fury, that they were responsible for whatever happened next.

Banks and Wigmore found the situation profoundly comic. Their campaign had fought against such “lies.” A vote to leave the E.U. would not mean panic in the markets, or the collapse of British prosperity. Laughing, they assured the man that nothing of the sort would happen. Banks handed him the bottle of champagne, and urged him to celebrate. As Banks recalled it, “He genuinely thought the world was going to come to an end!”

Banks told me this story, alongside Wigmore, on a rainy November afternoon two and a half years later, at 5 Hertford Street—a private member’s club, in Mayfair, where male guests are required to wear a formal jacket. The Brexit project that they had so ardently supported had left the U.K. in a state of panic. The government of Prime Minister Theresa May had almost imploded several times. The withdrawal agreement that May had made with the E.U., which was intended to smooth the transition for both parties, pleased nobody, and the deadline for Britain’s departure was approaching with the speed of a meteor. (Earlier this month, the impact seemed to have been slightly delayed when Parliament voted to postpone the onset of Brexit, originally set for March 29th, for a few weeks.) May was stuck in a dismal spot: if she couldn’t get a deal ratified by Parliament, Brexit might well occur with no transition at all. Many economists believed that this scenario, known as “no deal,” would shake Britain, causing upheaval at its borders and shortages of food and medicine.

This outcome was Banks’s preferred result. “No deal means we leave,” he told me at the club.

Banks was singularly calm about Brexit, but he had to contend with some issues of his own. At the request of the Electoral Commission, which oversees voting in the U.K., he was under investigation by the National Crime Agency—Britain’s version of the F.B.I. The commission had asked the agency to investigate Banks and his chief executive, Liz Bilney, after concluding that, among other things, Banks was likely not the true source of all the political contributions made in his name, and that he and others might knowingly have concealed the provenance of those funds. It is illegal in the U.K. to use foreigners’ money in electoral campaigns. “A number of criminal offences may have been committed,” the commission declared. A spokesperson told me that Banks’s and Bilney’s stories had “changed over time,” and that what they told the commission was “not consistent” with company records. (Bilney says that this “evolvement of response” can be ascribed to the commission’s failure to understand “our business structures.”)

A sense of urgency attended the National Crime Agency’s investigation, in part because of widespread fears in the U.K. that foreign actors had meddled in the Brexit vote. Although President Vladimir Putin has claimed that Russia was ambivalent about the Brexit referendum, he recently pressed May to “fulfill the will” of the British people and rule out a second referendum on the U.K.’s membership in the E.U.—which, polls suggest, would lead to a narrow win for Remain. Moreover, several authorities on Russian foreign policy argue that Putin’s interests are squarely aligned with the Leave movement. Putin, they maintain, considers it strategically useful to weaken European alliances, and is happy to cause uncertainty and tumult in Britain, which has been at odds with Russia on a range of issues. In 2016, for instance, Russia was under sanctions from both the European Union and the United States for its annexation of Crimea.

According to Andrew Weiss, a Russia expert at the Carnegie Endowment, Russian officials believed that the West had been pursuing a “regime-change agenda” around the world, particularly in Ukraine in 2014, and worried that Putin’s regime might be targeted next. “Russia felt they needed to push back hard,” Weiss told me. “They wanted to promote cleavages in the West, and that’s where their promotion of populist and nationalist groups and—I think—their support of Brexit fits in.”

Banks’s wife, Katya, is Russian. A prominent “ambassador” for Leave.EU, Jim Mellon, whom Banks has described as a “friend and business partner,” made much of his money by investing in Russia. (A representative for Mellon denied that Mellon has had a “close business or professional relationship” with Banks.) Banks’s 2016 memoir, “The Bad Boys of Brexit,” acknowledges that before the referendum campaign he met with Russian officials, including Alexander Yakovenko, the Russian Ambassador to London. Subsequent reporting has uncovered several other previously undisclosed meetings and contacts between Banks and Russian businessmen, during which opportunities with Russian firms in the mineral sector were discussed. In light of these connections, and the National Crime Agency’s investigation, many Britons have asked whether some of Banks’s political donations can be traced to Moscow. Alastair Campbell, Tony Blair’s former communications chief, and an ardent Remainer, told me, “There are still so many questions unanswered about Banks—where the money came from, and his role in the Brexit campaign of lies and misdemeanors.”

“I’d go see if it’s a burglar myself, but you know how I don’t like confrontation.” Facebook

Twitter

Email

Shopping

The government of the U.K. has been strikingly muted in its response to the evidence of contacts between Banks and Russian diplomats. According to various reports, in the early months of 2016, while Theresa May was Home Secretary, she refused a request by British intelligence services to investigate Banks’s conduct. Since becoming Prime Minister, that July, she has repeatedly declined to comment on these reports—including in Parliament. The subject is a delicate one for May. Although she campaigned for Remain, she has governed on the principle that Brexit is the people’s choice and must be enforced. Given the tensions surrounding the referendum, she is unlikely to invite further probes into the financial background of one of the Leave campaign’s key players. Doing so would be tantamount to using a grenade in a pub brawl.