Barton graduated in 1972 from Aledo High School in Aledo, Texas. He received a Bachelor of Arts degree in religious education from Oral Roberts University in 1976.

After graduating, Barton served as a church youth director. He taught math and science, and eventually became principal at Aledo Christian School, a small (less than 100 students) Christian school which grew out of Aledo Christian Center, a church started by Barton's parents.

In 1987 Barton formed Specialty Research Associates, which "focuses on the historical research of issues relating to America’s constitutional, moral, and religious heritage." Specialty Research Associates has submitted amicus curiae briefs in a number of court cases.

Barton is the founder and president of the Aledo-based group WallBuilders, an organization which presents "America's forgotten history and heroes, with an emphasis on the moral, religious, and constitutional foundation on which America was built." WallBuilders publishes and sells most of Barton's books and videos, which include Barton's position that the modern view of separation of church and state is not consistent with the views of the Founders.

Barton is married and has three grown children, including a daughter who does minority outreach for the Republican Party of Texas.

Barton is a former Vice Chairman of the Texas Republican Party. Barton has also acted as a political consultant to the Republican National Committee on outreach to evangelicals.

Barton serves on the Board of Advisors of the nonprofit National Council on Bible Curriculum in Public Schools organization, publisher of a controversial Bible curriculum for use in public schools (not to be confused with The Bible and Its Influence curriculum). This curriculum contains a number of direct quotations from Barton's books, as well as recommending the resources published by WallBuilders, and advocates showing that group's video, Foundations of American Government, at the beginning of the course.

One of the WallBuilders speakers is Rick Green, a former Republican member of the Texas House of Representatives and a candidate for the Texas Supreme Court in the April 13, 2010 runoff election.

Barton serves on the Board of Advisors of the Providence Foundation. According to its website, the Providence Foundation is a nonprofit Christian educational organization whose mission is to spread liberty, justice, and prosperity among the nations by instructing individuals in a Biblical worldview. Emphasis is upon educating in principles, rather than issues, drawing upon examples in history for illustration. In an article discussing Barton, The Nation described the Providence Foundation as "a Christian Reconstructionist group that promotes the idea that biblical law should be instituted in America."

In Barton’s book The Myth of Separation, the author states his belief that Christians were the ones who were intended to hold public office. Thus, Jews and other sects were not allowed to serve as elected officials. According to Skipp Porteous of the Massachusetts-based Institute for First Amendment Studies, Barton was listed in promotional literature as a "new and special speaker" at a 1991 summer retreat in Colorado sponsored by Scriptures for America, a far-right Christian Identity ministry headed by Pastor Pete Peters, which has been linked to neo-Nazi groups. However, Barton claimed that he was unaware of the group's anti-semetic and racist views at the time and since then he has written several articles that portray Jewish commentators and the Jewish people in general in a positive light.

Barton is a lecturer for Glenn Beck's online Beck University.

Barton received two Angel Awards (awarded to "people in any form of the media who have successfully contributed to the advancement of quality in life without the unnecessary need for violence, profanity and sexual content to sell to their audience") from the group Excellence in Media. He has appeared in Time magazine, and has been a guest on Trinity Broadcasting Network, The 700 Club, Fox News Channel, ABC, and National Public Radio.

Barton's work has been well received by many fundamentalist Christians and political conservatives, but he has received harsh criticism from secular groups and professional historians:

Senator Sam Brownback praised Barton’s work for providing "the philosophical underpinning for a lot of the Republican effort in the country today...bringing God back into the public square."

Richard V. Pierard, Stephen Phillips Professor of History at Gordon College describes Barton's work as follows:

Writing in the Harvard Journal of Law & Public Policy, (then Republican) Senator Arlen Specter stated:

First Muslim Congressman Claims

In 2007 Barton published an article purporting that founding-era Senator John Randolph of Roanoke of Virginia was actually the first Muslim member of Congress. The claim was made in reaction to the recent election of Keith Ellison (D-MN), a practicing Muslim. Barton's claim garnered widespread coverage in the evangelical Christian media at the time, but appears to have been based on a misinterpretation of a passage in which Randolph reported a youthful flirtation with agnosticism and professed sympathy for the Muslim Arabs during the crusades. Randolph was a practicing Episcopalian for most of his life, and his biographers reject Barton's claim about an Islamic conversion outright.

Unconfirmed Quotations

In an article titled "Unconfirmed Quotations," Barton conceded that he has not located primary sources for eleven of the alleged quotes from James Madison, Thomas Jefferson, Benjamin Franklin, and U.S. Supreme Court decisions (hence, the title of the article), but maintained that the quotes were "completely consistent" with the views of the Founders. This drew heavy criticism from Rob Boston of Americans United for Separation of Church and State, who accused Barton of "shoddy workmanship", and said that despite these and other corrections, Barton's work "remains rife with distortions of history and court rulings". WallBuilders responded to its critics by saying that Barton followed "common practice in the academic community" in citing secondary sources, and that in publishing "Unconfirmed Quotations," Barton's intent was to raise the academic bar in historical debates pertinent to public policy.

Barton has denied that the modern notion of separation of church and state exists, saying that, in Thomas Jefferson's letter to the Danbury Baptists, "Jefferson referred to the wall of separation between church and state as 'one-directional'...that is, it was meant to restrain government from infringing on the church's domain but not the other way around. There is no such language in the letter." However, this denial is contradicted by a 1990 version of Barton's video America's Godly Heritage in which Barton states:

Barton was also criticized for speaking at two functions that were organized by Christian Identity adherent and Holocaust denier Pete Peters' ministry, although he later stated that he "didn't know they (the groups he spoke at) were part of the Nazi movement".

Barton's legitimacy was reported to be growing in 2006, due largely to his first work which was not self-published, a 2003 article in the Notre Dame Journal of Law, Ethics and Public Policy, (Volume XVII Issue No. 2, 2003, p. 399), a "rather tame survey" on Jefferson’s writings about the First Amendment.

Criticism

Rob Boston of Americans United for Separation of Church and State has been critical, stating

The Religious Right's leading practitioner of this type of historical revisionism is David Barton ... Barton makes a lucrative living traveling the right wing's lecture circuit where he offers up a cut-and-paste version of U.S. history liberally sprinkled with gross distortions and, in some cases, outright factual errors. Crowds of fundamentalist Christians from coast to coast can't get enough of it.

Rev. Randolph Bracy, president of the Orange County, Florida chapter of the NAACP has referred to Barton as a "Holocaust-denier, an anti-Semite and someone who has called for the death penalty for gay and lesbian people", stating that Barton has "a long history of being related to the worst fringes of our society."