President Donald Trump kicked off this week by talking about how the slave-owning, ethnic-cleansing seventh president of the United States could have saved the country from plunging into a bloody civil war.

In an interview with Salena Zito for “Main Street Meets the Beltway” on SiriusXM P.O.T.U.S. that published Monday, Trump returned to an earlier habit of heaping praise upon President Andrew Jackson—and, of course, discussing how Trump himself is Andrew Jackson 2.0.

“They said my campaign is most like, my campaign and win, was most like Andrew Jackson with his campaign,” Trump boasted, talking up Jackson the “swashbuckler,” as Trump characterized the controversial figure.

He then went on a somewhat bizarre tangent about the Civil War and Jackson’s supposed deal-making prowess and compassion.

“Had Andrew Jackson been a little later you wouldn’t have had the Civil War,” Trump said. “He was a very tough person, but he had a big heart. And he was really angry that he saw what was happening with regard to the Civil War, [and] he said, ‘There’s no reason for this.’ People don’t realize, you know, the Civil War, if you think about it—why? People don't ask that question, but why was there the Civil War? Why could that one not have been worked out?"

The short answer is, of course, slavery . And other U.S. politicians have asked that question in recent years, such as libertarian and Tea Party figure Ron Paul , who argues that the United States could have ended slavery without waging war.

Jackson died years before the American Civil War began, but Trump’s remarks likely reflect the 45th president’s cursory knowledge of Jackson’s administration and legacy, which includes Jackson’s handling of the Nullification Crisis of the 1830s. The outcome of the crisis averted a violent civil conflict that would have occurred decades before Abraham Lincoln set foot in office.

If you’re wondering why Donald Trump enjoys chatting about Andrew Jackson so much, the answer to that question is Stephen Bannon, the chief strategist in the Trump White House.

As The Daily Beast reported in March , Bannon has, since the 2016 presidential campaign, actively pushed Trump to learn more about Jackson and to play up comparisons, however flawed, between Jackson’s populism and Trumpian nationalist-populist rhetoric and themes. In March, Trump even made a high-profile visit to Jackson’s Nashville tomb, where Trump solemnly saluted the deceased president.

President Trump’s love affair with the ghost of President Jackson is a relatively newfound one. For instance, @realDonaldTrump’s only other pre-2017 tweet about Jackson was tweeted in July 2013, when he wrote : “Interesting… the last time a Democrat succeeded a two-term Democratic pres. was in 1836 when Martin Van Buren succeeded Andrew Jackson.”

Bannon, the former head of Breitbart and a longtime “ history nerd ,” would often discuss Jackson’s historical legacy and image with Trump on, and after, the campaign trail, and how the two political figures had a lot in common, according to officials in the Trump campaign, presidential transition, and administration speaking to The Daily Beast .

“[During the race], Trump would say he had heard this pundit or this person making the comparison, and [Steve] would encourage him and tell him how it was true,” a Trump campaign adviser, who requested anonymity to speak freely, said in March. “It was a way to flatter [Trump], too. Bannon and Trump talked about a lot, but this was the president they had casual [conversations] about the most.”

According to two sources with knowledge of the matter, Bannon had suggested and had given Trump a “reading list” of articles and biographies on Jackson, and literature on Jacksonian democracy and populism. Stephen Miller, another top Trump adviser, also recommended and offered related reading material to Trump, one senior Trump administration official said.

“[Trump] has read other biographies and articles [on Jackson] and has taken a strong interest,” the official said.

Bannon, himself a Jackson buff, reportedly co- wrote with Miller most of Trump’s inaugural address—a speech Bannon said in January was “given, I think, in a very powerful way. I don’t think we’ve had a speech like that since Andrew Jackson came to the White House. But you could see it was very Jacksonian.”

It was only a month ago that many pundits and reporters were prematurely writing Bannon’s political obituary amidst wide speculation that, due to “nonstop” White House infighting , the chief strategist’s days working in the administration were suddenly very much numbered. Still, whatever happens to Bannon and his West Wing allies in the near future, President Trump’s Andrew Jackson obsession is one of many ways that Bannon has left his mark on the Oval Office.