This is exactly the sort of thing I’m talking about: confidently firing off a mix of half-remembered and out-of-context factoids with “lies and coverups in history!!!” to make them seem like they’re correcting the record rather than reducing a mix of truth, common misconceptions, conspiracy theories, misunderstandings, and poor reporting to pithy one-liners. Let’s go through them.
Brits in the 1800s used to eat Egyptian mummies,
It's complicated. There's definitely a grain of truth to this, but it's not quite what the common narratives suggest. For example, eating mummies was a Medieval thing more than it was a Victorian thing; Victorians did "Scientific" mummy-unwrapping parties, but they didn't then eat them - they were collectible antiquities. For another, the mummies used by Victorians for paint were rarely ancient Egyptian humans. I'll let @thatlittleegyptologist take this one because they've talked about it. A lot. Like a lot. So often.
numerous gay relationships in history were called “friendships” by Christian historians,
It's complicated. Have historians in the past denied that their favorite historical figures could possibly be gay? Absolutely. But people who were romantically and sexually involved with each other in the past very often did call each other "friend." (Or, in ancient Egypt, "brother"). Even husbands and wives would call each other "friend." (it's midnight and I am blanking on how to search for sources that show this but I have transcribed 18th century letters and diaries, I have seen this.) Like, while historical squeamishness and denial of gay relationships has been a thing... the modern assumption that friendship cannot possibly ever include any gay stuff is also not helping. And heteronormatively taking words at face value is somewhere in between. It's sometimes malicious, but you have to give space for simple hetero brain too. And give space for all the queer and queer-affirming historians working in the field. And for people like Oscar Wilde who were arrested for sodomy and the Ancient Greeks who were Ancient Greek so it's hardly like anyone's denying that, even if their interpretation was that it was Bad. It's not cut and dry.
the Vatican is hoarding almost all history ever written and refuses to let anyone access it,
This one isn't actually complicated, it's just a bizarre misunderstanding (generous interpretation) or an Evangelical conspiracy theory (less generous interpretation) of what the Vatican Apostolic Archive, formerly known as the Vatican Secret Archive, is. They're not "hoarding almost all history ever written" (how would that work?). It's an archive of the Church's and the Vatican's records, accounting, correspondence, declarations, decisions, and other various affairs. Over the past several hundred years of dutiful documentary-keeping, that does add up to a lot of history about the development of European politics, culture, and colonization! There are in fact two archives; one which has been accessible to scholars since 1881, and one which is owned unilaterally by the Pope and only extremely rarely opened for any sort of access to outsiders. John Paul II actually made it easier for researchers to access those archives, though "easier" does not mean "easy" and is still very much at the Pope's discretion. However, they are archives pertaining to the Pope's and Church's affairs, not all of human history.
the original biographies of the Sons of Liberty were all works of fiction (like Washington and the apple tree),
True! But also a little complicated. The story about Washington and the cherry tree is complete fiction, and we know who to blame for it: Mason Locke "Parson" Weems, who wrote his famous biography of Washington right after Washington died and the nation was clamoring for tributes to him. He was kind of shameless about writing for the masses things that would sell. But at the same time, it was part of the myth-making of the new nation, part of a very common process at the time of nearly deifying Washington. But it is also true that we do in fact have a lot of letters and diaries written directly by these guys. We don't need to rely on Weems for fanciful stories about them, even if they have entered into the mythology-building of the US as a nation.
Greek and Roman statues were painted but the people who discovered them found it garish so they stripped the paint off,
Have you ever seen what happens to painted stone when left out in the elements over time? The paint chips off. Being exposed to the elements or buried in the dirt for hundreds or thousands of years does a number on the painted exterior of a statue. Here's a Jesuit scholar from 1913 lamenting this: "It is a notorious fact that the remains of colour fade very fast from marbles that are exposed to the light after centuries of burial and concealment. It is the universal experience of classical archaeologists. A French explorer describes some colours vanishing from sarcophagi found at Carthage "comme de la fumée" [like smoke]. Add to this the perfectly intelligible cleaning consequent on first discovery in the earth, and the still more disastrous and less pardonable washings with acid that, until recent years, were the fate of all classical statues. Even still another risk has to be remembered, the taking of casts […] Add these fates together, and say whether their total does not offer an explanation for a prejudiced view." Honestly, as Gisela M. A. Richter (1944) says, "The fact that any color at all remains is really more remarkable than that it has disappeared in the majority of cases." Greek and Roman statues, probably even marble statues, were painted! Yes! But there was probably little paint remaining even when the Renaissance sculptors and art collectors got ahold of them. And while the discoverers deliberately stripping off the paint because they decided it should not have been there is one potential reason (note the reference to acid-washing), and the pure white marble was a very ideologically-loaded Enlightment-era aesthetic highlighting the purity of the form, and 1700s-1800s English archaeologists and antiquarians had vicious debates over whether the marble statues were painted like the fate of their cultural hegemony rested on it, "removing the paint for its garishness" was not even close to the primary reason the colored paint does not remain. These are some resources about the Gods in Color exhibition that did experimental reconstructions of the colors of some statues.
Leonardo da Vinci drew designs for many devices, including a war machine that does resemble a modern tank! It's frequently described (with hedging descriptions) like "has been seen as a prototype of a tank." But there's no evidence that it was ever built, and it's unclear if the wheels and gear system would have worked. Can he be said to have "invented a tank"? I guess it depends on your definition of "invented."
Lancelot is a fanfiction OC,
This is either a flippant or deeply disingenuous way to describe the origins, evolution, and recording of King Arthur mythology, its use in literature and nationalist propaganda, and the way this is different from the way fanfiction interacts with a canon. @chimaerakitten knows much more about this than I do.
and the Catholic Church was founded after numerous other Christian churches and proceeded to burn the holy books that didn’t support their version (like the Gospel of Judas, which establishes that the “betrayal” was Jesus’s plan because how was he supposed to die as planned, and they plotted it together).
Ohhhh boy it's complicated. I am out of energy and by god it is late but there is a reason that books and books and books have been written about the history of Christianity, the early schisms, the creation of the canon, Gnosticism, and the origins of the Catholic Church.
Basically: if it can be summed up in one sentence as a "gotcha!" it is probably More Complicated Than That.
