Other Official Histories.
The rough conclusion this short list following might suggest is that such official histories can be widely believed, even when they are easy to discredit. The successful ones, like conspiracy theories, tell a story people want to believe. There may be more suspicion when an official history is hard to discredit, but doesn't recite what many people want to believe.
So I can believe that an Official History of the Troubles, written as many mainland British in their national pride would like to believe it, would actually become some kind of a widely accepted version, but only on the eastern side of the Irish Sea. It would doubtless bare our souls as to how evil the British have been to the Irish for most of past millenium. But the various brief exposures of the utter wrong-headedness, and perfidiousness of the British govt, like bl..dy Sunday, during the actual Troubles will doubtless come out as isolated "mistakes". Because the alternative is not consistent with the national epic of the British.
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The Gunpowder Plot. It is common to refer to an Official Version, even the
UK Parliament Website mentions it, though I'm not sure precisely what documents it entails. I think most British people do take the standard recitation broadly as fact. But my history teacher at (high) school told us, as fact, it was a whitewash. He then spun us one of the popular conspiracy theories. He was sensible enough to say this was just one possibility, and not advisable to write it as fact in an exam, or indeed take any notes on it in our exercise book. I was later surprised to discover that such versions were not at all popular with reputable scholars. It did at least introduce me to the concept of source criticism. The confessions were doubtless extracted by torture, and so do not meet modern evidential standards. There are reasonable doubts about the authenticity of the Monteagle Letter, even UK Parliament mentions that. So doubtless the standard version cannot be relied upon. But the conspiracy theories are even less likely.
JFK Assassination. The Warren Commission. Most Americans don't believe it, nowhere near. So the US Govt has revisited it at least twice to try and get some kind of supportable consensus, but with little success. Even I used to find it very hard to believe that Jack Ruby acted alone. But some kind person on the predecessor of this forum explained the logical error I was making.
The Official History of the Communist Party of China. Nasty things happen to people in China if they dare to question it in ways that get attention. But such repressive methods are actually quite successful, in their own terms, and I think most Chinese people do broadly believe it. From my own experience of trying to discuss it with recent immigrants from mainland China, they have denied the modern western histories as implausible. In the early days, the Party even managed to get seemingly reputable but sympathetic western historians in to regurgitate the official version back to the world, so even we widely believed it. It is only more recently that imperialist degenerate historians like Frank Dikotter have dared to examine the official archives during periods of relative glaznost, and thus demonstrated that it really wasn't like that at all.
The History of the Kings of Britain by Geoffrey of Monmouth (ca 1136). Was generally accepted as accurate history for about 400 years. We now realise that Britain was not founded by Brutus the Trojan, King Lear is made up, and almost all of the book is on that level.
Kebra Negast. Meanwhile over in Ethiopia/Eritrea, their own 14th century own national epic whose title translates to roughly the same as Geoffrey's, is more or less taken as truth by most highland Ethiopians and Eritreans. Numismatic evidence finds no overlap between rulers that there is actual evidence for, and those mentioned in the work.
The usual history as taught in British schools in more modern times. There have been various TV programs in recent years showing how completely wrong are the standard recitations of key defining points in our national history like the Spanish Armada, etc. So the bastards did succeed in foisting lying official versions on us all even in much more recent times.
Religious texts, those that contain "history". 'Nuff said.