I don't think there was any question as to what the amendment meant prior to the 1960s. Schools and media have done a fair job of convincing people otherwise since then.
When I was in law school (University of Texas) in the 1960's, the 2nd Amendment wasn't even mentioned in my Constitutional Law class. It was generally considered to be a dead letter. Probably the only organization talking about the 2nd Amendment then was the National Rifle Association.
That began to change among the legal profession in the decade of the 80's. A watershed event was the 1989 publication of an article by Sanford Levinson (a professor at the UT Law School) in the Yale Law Journal, entitled "The Embarrassing Second Amendment." Levinson, a gun control advocate, reluctantly concluded that the RKBA was an individual right.
Here's a summary of the debate among legal scholars and historians around that time (this was before the
Heller decision):
Against their own liberal political inclinations, some legal scholars have reluctantly concluded that in its claim that the Second Amendment protects individual Americans’ right to bear arms, the National Rifle Association is not far off target.
"A well-regulated Militia, being necessary to the security of a free State," the amendment famously states, "the right of the people to keep and bear Arms, shall not be infringed." To University of Texas law professor Sanford Levinson, a liberal Democrat who backs many gun control measures, the "embarrassing" Second Amendment (as the title of his seminal 1989 Yale Law Journal article put it) empowers individual citizens to own guns to defend themselves and, if necessary, counter government tyranny. This individual right to bear arms, adds Joyce Lee Malcolm, a historian at Bentley College in Massachusetts, traces back to the 1689 English Bill of Rights.
In recent years, legal scholars--including Laurence Tribe, the prominent liberal Harvard University professor of constitutional law--"have turned en masse" to this "individual rights" reading, making it the so-called Standard Model interpretation of the amendment, reports Mooney, a freelance writer based in New Orleans. Alluding to this scholarship, a federal district court judge in Texas last year "delivered an unprecedented ruling in defense of the individual’s right to bear arms," says Mooney. If the ruling survives an appeals court’s decision this spring, the case may well go to the Supreme Court.
But some American historians now contend that the Standard Model interpretation--which regards "militia" as standing, not for a select group like the modern National Guard, but rather for "the whole people"--is at odds with history. Saul Cornell, of Ohio State University, questions whether any consensus existed in post-revolutionary America on the right to bear arms. In Pennsylvania, he notes, a stringent loyalty oath effectively disarmed up to 40 percent of the citizenry. Michael Bellesiles, of Emory University, maintains that only a small percentage of Americans then even owned firearms--only about 14 percent of white, Protestant men in New England and Pennsylvania, according to 11,000 probate records filed between 1765 and 1850.
http://archive.wilsonquarterly.com/in-essence/embarrassing-second-amendment
