“Oliver Stone’s Untold History of the United States,” a documentary series that debuts Monday on Showtime, focuses on Henry A. Wallace — former agriculture and commerce secretary, as well as Franklin D. Roosevelt’s vice president — as its protagonist over the first three installments. (Harry S. Truman Library)

It’s somehow appropriate that Oliver Stone has chosen a hotel just a few blocks from the Agriculture Department to talk about his new project. “Oliver Stone’s Untold History of the United States,” a documentary series that debuts Monday on Showtime, focuses on Henry A. Wallace — former agriculture and commerce secretary, as well as Franklin D. Roosevelt’s vice president — as its protagonist over the first three installments, which suggest that the Midwestern statesman would have put America on a radically different trajectory had his path to the presidency not been blocked by Democratic Party leaders in 1944.

Stone’s interest in Wallace was sparked during a 1996 visit to American University, where history professor and “Untold History” co-writer Peter Kuznick was teaching a course called “Oliver Stone’s America.” At dinner that night, Kuznick “was talking about the atomic bomb and how it got started and the scientists and Henry Wallace,” Stone recalled Friday, “but I wasn’t in the mood to take on the establishment again, because ‘Nixon’ had not done as well commercially as I had hoped. That was a big effort, it had wiped me out. But [the Wallace episode] was a dark and difficult story, really good. It stayed with me.” Ten years later, Stone visited Kuznick’s class again. “I said, ‘Look, I can’t get that story out of my mind. Let’s do a documentary, an hour or an hour and a half.’ And unfortunately, my eyes were bigger than my stomach.”

“Oliver Stone’s Untold History of the United States” runs over 10 one-hour episodes, beginning in World War II and continuing through the Obama administration. With newsreel footage, copious research and Stone’s own understated narration, “Untold History” revisits familiar events, but through an unapologetically leftist lens. While “Untold History” is grounded in indisputable fact, some of its contentions will certainly give conservatives and even moderate liberals pause, including its championing of Wallace, who has been castigated in recent years for what critics see as an appeasing attitude toward Soviet leader Joseph Stalin and surrounding himself with communists.

Stone grows visibly frustrated when considering these naysayers. “Do you want to deal with it academically?” he asks Kuznick. “I would deal with it emotionally. You go first.”

Kuznick jumps in. “There are times you can say he’s a little naive about Stalin — like most Americans, he didn’t realize the depth of Stalin’s brutality, and I think that’s a fair criticism,” he says. “But . . . in terms of his view of the world, and in terms of trying to change the world for the better, I think he was absolutely a visionary. What makes him different is that he could see what was happening in the world through Russian eyes, through Chinese eyes, where most Americans can only see the world through U.S. eyes.”

If “Untold History” makes a plea, it’s for American viewers to reassess that point of view and to question some of our most cherished assumptions, from how World War II was won (hint: the Soviets deserve far more credit than the A-bomb) to the notion of American exceptionalism itself. Stone, who was born in 1946 and fought in Vietnam, noted that “Untold History” spans his own lifetime, during which his personal changes largely mirrored those taking place in the country around him.

“You have to realize, I was sleepwalking until about 1968,” he said. “And then from ’68 to ’79, it was a period of waking up, but not completely. Then in the ’80s, again [I was] more exposed to the world [with] more travel. And by the time I met Peter, I was really finally learning on a deeper level than I’d ever learned before. It feels good, in that I feel that my consciousness is expanding, but sometimes to my detriment. . . . You’d like to believe in the magnanimity of our leaders and the myth of American goodness.”

In many ways, “Untold History” encapsulates the long-standing argument between security interests and humanist ideals that defines postwar American policy, with Stone and Kuznick coming down firmly on the side of a more global, less solipsistic national posture. When asked what he would do about Iran and nuclear weapons, for example, or the plight of a Pakistani teenager shot by Islamic fundamentalists for supporting girls’ education, Stone spells it out. ­“L-A-W,” he says. “International law. Because there has to be a consensus of nations. Roosevelt’s ideal was that the U.N. can work, and it still does. . . . I believe in national sovereignty, I’m an old-fashioned guy. But I would take the judgment of 185 nations. They have a better sense of the world than we do by ourselves. So let’s make [the U.N.] work as a council of nations. It’s hard to do, but it can be done.”

It goes without saying that “Untold History” won’t end up on John Bolton’s 10-best list of the year. But in hewing faithfully to the facts — albeit within a dramatically different framework than most Americans are accustomed to — Stone can’t be accused of the kind of speculation and expressive interpretation that upset so many viewers of “JFK,” his 1991 film about the assassination of John F. Kennedy that he made as a “counter-myth” to the Warren Commission.

Kuznick notes that “Oliver is often dismissed or denigrated as a conspiracy-monger. . . . What this project can do is show people what a serious thinker he actually is.”

If Stone doesn’t see the world in terms of conspiracies, there’s no doubt that he does see it in terms of unseen forces — political, corporate, psychological — that shape our society in ways we can’t know, at least until he pulls back the veil, whether in presidential dramas such as “Nixon” and “W.” or documentaries such as “Comandante,” about Fidel Castro, or “South of the Border,” about South and Central America. He’s happy that Barack Obama was reelected, he says, but he’s profoundly concerned about the 44th president’s embrace of electronic warfare and an approach to foreign relations that, in Stone’s view, is far too militaristic.

The filmmaker noted that in the 750-page companion book to the “Untold History” series he co-wrote with Kuznick, the chapter about Obama is subtitled “Managing a Wounded Empire.” “I think he’s a good manager of that,” he says, “but I don’t expect anything.” Then again, he added upon reflection, “Robert Kennedy was prosecuting [with Joseph] McCarthy, and look where he ended up.”

“Oliver Stone’s Untold History of the United States” airs Monday at 8 p.m. on Showtime.