Burr is the first novel (although not the first published) of Vidal's Narratives of Empire series of seven historical novels. It generally presents its namesake character as a fascinating, heroic, and fairly honorable gentleman, while skewering most of the other U.S. historical figures who appear in the story, including George Washington (whom Burr remembers as an incompetent general on the losing side in most of his battles in the American Revolution) and Thomas Jefferson, with whom Burr tied for president in the election of 1800. The novel's portrait of Jefferson is especially dark; he is painted in Burr's memory as a pedantic hypocrite who schemed and bribed witnesses to support a false charge of treason after Burr almost defeated him in the Presidential election. Another target is Alexander Hamilton, a "bastard" (he was born illegitimate) opportunist whose star rose with Washington's before he was killed by Burr in the famous duel, one of many historical incidents that Burr's character recounts in the last years of his life in the novel.
Like Vidal's historical novels Julian and Creation, Burr contains an imaginary memoir. In fact, Vidal did meticulous research of hundreds of documents to come up with his alternative reading of history. In an afterword, the author maintains that in all but a few instances, the characters' actions and many of their words are based on actual historical records.
Indeed, the election of 1800 did result in a tie between Aaron Burr and Thomas Jefferson, and it took more than 30 ballots in the House of Representatives before Jefferson become president and Burr his vice president (as mandated by the election rules at the time). Many other incidents in the novel are verifiable in the historical record, including Jefferson owning (and probably fathering) slaves, James Wilkinson serving as a double agent for Spain, Alexander Hamilton being challenged to duels by opponents who felt slandered by him, and Burr's trial and acquittal on charges of treason. There are also many parallels in the novel to Aaron Burr's real memoir, written by Matthew L. Davis and published shortly after Burr's death.
The narrator in Burr is the fictional Charles ("Charlie") Schuyler, a young man of Dutch descent working as an apprentice in Burr's New York law office some 30 years after the treason trial. Charlie is not from a political family and is ambivalent about politics and practicing law. While procrastinating over the bar exam, he writes stories for newspapers and dreams about being a successful writer so he can move to Europe.
A major plot thread involves Vice President (and presidential candidate) Martin Van Buren, who is rumored to be Burr's illegitimate son. Charlie is enlisted by Van Buren's political enemies to glean facts about Van Buren from Burr. He is tempted by the promise of a fortune if he writes a pamphlet proving that Van Buren is Burr's bastard son, which would ruin the future president's political career. He is torn between honoring Burr, whom he admires, and gaining a fortune to take the woman he loves away to a new future. In the end, Charlie learns more than he could have imagined about Burr, Van Buren, and about his own character.
Perhaps the most controversial aspect of the novel is the premise that the "despicable" gossip spread by Hamilton which led to his death by Burr's bullet was that Burr had practiced incest with his beloved daughter, Theodosia. Though purely the speculation of author Vidal (albeit not after some consideration of the evidence and probability), this ultimately fictional and unprovable plot device has been repeated as factual on the Internet and in less scholarly works.
Burr is the first in a series of novels in which Vidal follows generations of a fictional family through the history of the United States. The third book in the series, 1876, tells of Charlie Schuyler returning to the United States after having spent nearly forty years in Europe.