“Gates recalled Manafort saying the hack was likely carried out by the Ukrainians, not the Russians, which parroted a narrative Kilimnik often supported,” reads a memo summarizing an April 2018 FBI interview with Gates, who cooperated with federal prosecutors and testified against Manafort in exchange for a more lenient sentence.

It’s not clear whether Trump was aware of Manafort’s alleged claims. During the campaign, the candidate largely cast doubt on Moscow’s meddling, the full extent of which was not yet known.

“I don't think anybody knows it was Russia that broke into the DNC,” Trump said at the first presidential debate on Sept. 26, 2016. “I mean, it could be Russia, but it could also be China. It could also be lots of other people. It also could be somebody sitting on their bed that weighs 400 pounds, OK? You don’t know who broke into DNC.”

In January 2017, however, when POLITICO published a story titled “Ukrainian efforts to sabotage Trump backfire,” some of Trump’s allies seized on elements of the reporting— sporadic criticism of the Republican candidate by Ukrainian officials and meetings with a DNC consultant—while ignoring the caveat that the investigation found “little evidence of such a top-down effort by Ukraine.”

Once he was sworn in, Trump had unfettered access to the unclassified intelligence that informed the intelligence community’s conclusion that Russia hacked the DNC and interfered to help him win. But he still refused to believe it, preferring the unsubstantiated rumors about Ukraine’s attempts to sabotage his candidacy.

“He would almost never not bring it up,” one former White House official said of Trump’s fixation with the Ukraine conspiracy theory. “And that certainly continued the whole time I was there. It was Ukraine, Ukraine, Ukraine. You just couldn’t make him understand that’s not how it turned out.”

Suspicion of Ukraine already ran deep among some of Trump’s top advisers, according to another former White House official. “Steve Bannon and Stephen Miller had an enormous amount of distrust and suspicion toward Ukraine,” the former official said, and thought the Ukrainians were trying to get the U.S. to be more adversarial toward Russia.

“I thought it was odd, because it seemed obvious that Ukraine was someone we needed to be closely allied with,” this former official said.

Early on in his presidency, Trump went as far as to ask the Justice Department, then helmed by Jeff Sessions, to investigate the issue of Ukrainian interference on several occasions, the formal official said. But DOJ would always decline, this person added, “because their sense was that Mueller was going to do it for them.” A DOJ spokesperson did not respond to a request for comment.

It would fall to Trump’s personal lawyer, Rudy Giuliani, to seek evidence implicating Ukraine in 2016 election meddling—a quixotic mission fueled by his client’s insistence on complete exoneration as his own administration deepened its probe into Russia’s very real involvement.

The origins of Giuliani’s private investigation are murky. David Ignatius, the Washington Post columnist, has pointed to June 2017 as the date when the former New York mayor traveled to Kyiv to meet with then-president Petro Poroshenko, who was scrambling to establish ties to the new U.S. president. There, Giuliani also met with Yuriy Lutsenko, the prosecutor who would later level various unsubstantiated corruption allegations against the Bidens.

For his part, Giuliani has described his efforts as an attempt to prove that Democrats “framed” Trump with the help of Poroshenko’s government, which both deny. “The collusion that they claim happened in Russia happened in the Ukraine with Hillary Clinton,” Giuliani has said.

It was clear to many government officials early on, however, that the theory was rooted in Russian disinformation and could even be part of an intelligence operation, said another person close to the White House. And intelligence officials have since briefed lawmakers on their belief that the theory is Russian propaganda, according to a person familiar with the briefings.

But Trump’s advisers soon gave up on trying to convince him of Russia’s role, said the first former official.

“Anything he associated with the intel community, he rejected pretty much out of hand because his sense was that the ‘Deep State’ had decided in some star chamber or secret meeting that they would feed intelligence to him that would cause him to make mistakes, and disprove a lot of his theories about what happened in the election,” the person said.