There's been discussion online about the language of the BBC's "Wolf Hall". Not, mercifully, about the headache-makingly unclear pronouns of the book (who he?), but about the very modern style. This extends into body language and attitudes. When the king, with power of life and death over his subjects, asks Cromwell why he called a French town "a dog hole", Thomas almost shrugs and says with a rising intonation, like an offensively casual teenager, "Because I've been there?" Also at Sir Thomas More's dinner table he asks if his host had become Lord Chancellor by "fucking accident". It sounds like a very modern and aggressive usage quite out of character for the cool, cautious Cromwell.
It has been pointed out, btw, that the f-word does appear in a 16C manuscript. But there it is a monk saying factually what the abbot was up to and is not used as an intensifying adjective. This latter usage may not have come in till the 19C, it seems. (Thanks to world expert on slang Jonathon Green @MisterSlang and to @LoisMcEwan on that.) Although they are often referred to as Anglo-Saxon, several four-letter swear words were not used as such until modern times.
I suppose the orthodoxy is to make historical figures human and, indeed, modern. Wouldn't it be more interesting, though, if they were strange and different, weird even, almost from another planet? After all, these were very superstitious people who believed in all sorts of supernatural and miraculous things and who thought hanging, drawing and quartering and burning alive were suitable judicial punishments. It is a bit like saying if you are teaching inner-city kids, you should read stories and poems about their type of lives and environment. But perhaps they would prefer something rich and strange? Philip Pullman novels come to mind.