Here is the quote:
The most effective way to destroy people is to deny and obliterate their own understanding of their history.
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Sign up to join this communityHere is the quote:
The most effective way to destroy people is to deny and obliterate their own understanding of their history.
The meaning of the quotation, I think, is essentially as A.P. puts it in a separate answer: History is cultural memory, and the loss of knowledge of one's history destroys one's sense of community and shared identity, casting one adrift in the present without meaningful reference points from the past. This is true whether one is an individual person or an entire population.
About the source of that quotation...
Since I claimed in an early comment above that this quotation was from George Orwell's Nineteen Eighty-four, I felt obliged to confirm that it really originated there; and since comments tend to vanish unexpectedly on this site, I want to post my findings in more lasting form as an answer, even though my focus is tangential to the poster's question.
The quoted sentence appears many, many times on the Internet, attributed variously to George Orwell, to George Orwell in 1984, and to George Orwell, author of 1984. But every repetition of the quotation that I've checked presents it without any context. This floating-in-the-void quality is characteristic of spuriously attributed quotations on the Internet—and very typical of the disturbing Internet echo chamber effect, in which people pick up and repeat quotations without confirming the accuracy of the wording against the claimed original source.
Two years ago a poster at AmazonNews's Open Study forum asked Kindle owners to search for the quoted sentence in Nineteen Eighty-four, and someone else responded that it simply isn't there. Here is the exchange:
jcarl: Would anyone have 1984 on Kindle or be able to help me find the page number for this quote??
Batbite: What quote?
jcarl: "The most effective way to destroy people is to deny and obliterate their own understanding of their history." I couldn't find the page number of this quote in 1984.
Batbite: I'm sorry but that quote is nowhere to be found in the book. I looked through it a bit as well and couldn't find anything similar to it either.
I'm guessing this quote is half fictional and half paraphrased.
My Internet search for the phrase "destroy people is to deny and obliterate their own understanding" yielded more than 70 unique matches, all attributed to George Orwell or, more particularly, to 1984—but none with any surrounding text included, and none with a page number or other specific citation. The earliest dated citation of the quoted sentence was from 2012 in a text that also shows up in a Google Books search, Filipinos of Greater Philadelphia.
A Google Books search for "destroy people is to deny and obliterate their own understanding" yields 14 matches—the earliest being, once again, Filipinos of Greater Philadelphia (2012).
Conclusion
It doesn't make a lot of sense that George Orwell would have managed to say something catchy that then went unremarked and unquoted during his lifetime and for 62 years after his death only to become widely quoted without a specific source reference. It is certainly possible that Orwell wrote a similar sentence and the sudden appearance of the version that the OP quotes is based on a slightly altered wording that appeared recently. But I ran searches for several strings of words from the sentence, and none of them turned up a significantly different original quote. So either the quotation is entirely unconnected to Orwell's writing or it substantially alters his original wording.
I suspect that the former explanation is the more likely one. And if the sentence isn't from Orwell, whoever first attributed it to him must have had a great sense of irony.
The most effective way to destroy people is to deny and obliterate their own understanding of their history.
This quote has been attributed to George Orwell and sounds a lot like his famous "Who controls the past controls the future; who controls the present controls the past" (a party slogan from 1984.)
The meaning here clearly applies to any society, not just to peoples (such as Native American tribes).
What the author is saying is that history is malleable. It is possible to shape it via education, indoctrination, and propaganda.
A people's history is their guide, their reference point. Take it away, and they are fumbling in the dark, susceptible to other agendas and ideologies. That, according to the author, is a sure way to control (or destroy) them.