The row over alleged historical inaccuracies in the BBC’s current dramatization of “Howards End” has struck a rich seam of concern among historically literate people regarding the inability of contemporary media to represent the past correctly. In this instance, however, the controversy appears to be a storm in a jam-jar with little evidence to support it.

The inaccuracies complained of were apparently the spectacle of one character holding a piece of toast in her hand and spreading jam on it with a spoon instead of a knife, as well as male characters wearing their hats indoors. Granted that in Edwardian times it would have been more usual (and practical) to place the toast on a side plate and spread the jam with a knife, no society can legislate for the universal practice of so minor an action: an individual, at any given moment, might easily have deviated from the general custom, especially someone of a bohemian background.

As for the hats, it is now claimed none of the male characters commits the solecism of remaining covered indoors in the television series and an expert cited as a complainant seems now to be saying the Daily Telegraph provoked the whole controversy in the first place. Clearly, this is not favourable ground on which to fight the battle over historical authenticity.

Nevertheless, that battle needs to be fought. With schools history reduced to “the Nazis” and slavery, television and cinematic period dramas are nowadays almost the sole thread connecting people today with the past. That makes it more important than ever that period dramas should represent that past accurately, in facts, costume and manners. Any society that is not firmly rooted is ill equipped to survive.

Hats, though apparently a mere distraction in the current controversy, are a crucial element. They are particularly tricky to get right because of changing customs over relatively short time spans in the past. It is true, of course, that no Edwardian gentleman would have worn his hat indoors. Yet just seventy years earlier the Duke of Wellington had critically surveyed the new intake of MPs in the first post-Reform Act parliament and observed: “I never saw so many shocking bad hats.”

The point is, he was in the Commons chamber when he made that damning remark: MPs at that time retained their hats indoors. They did the same in their clubs and other places of resort: caricatures of clubland in the early 19th century illustrate this habit.

It should be conceded that, in the matter of accuracy in historical costume, there has been a marked improvement on television over the past decade or so, especially with regard to the Regency period. An army of experts and historical advisers has sprung up, all with an encyclopaedic knowledge of women’s costume in particular; there are many online websites aimed at women which feature extremely recherché information regarding both male and female Regency costume.

Not long ago a girl seated next to me at dinner turned out to be studying the history of women’s costume at university: she confided the startling information that over the Regency period and the reign of George IV there were more than 30,000 different types of bonnet ribbon.

Behind this not-a-lot-of-people-know-that item of sartorial trivia lies a vast hinterland of trade, commerce, manufacture, employment and economic domino effects, as well as social history. It is time to expunge media studies from university curricula and have more undergraduates investigate the stomacher, the codpiece, the ruff, the bustle and similar accessories to the march of history.

In film and television drama the weakest link is the 17th century. About thirty years ago it became the fashion to allow actors playing cavaliers or musketeers to wear their own hair, never grown long enough, teamed with inadequate sub-Vandyck beards. The consequence was they remained quintessentially 21st-century men. A recent version of “The Three Musketeers” portrayed Dumas’ heroes looking more like a gang of bikers than elite royal guards.

The real problems, though, are not of costume but of script. A pre-Revolutionary French nobleman referring to “the underprivileged”, rather than the “canaille”, was the nadir of BBC anachronism. Language and, more importantly, its nuances, has changed radically over the years. Today we are further afflicted by a contrived Newspeak of PC moral hypochondria distorting everyday speech.

For scriptwriters trying to project themselves into the past – and that can mean the 1950s – the struggle to escape the gravitational pull of 21st-century language, an incongruous mix of crudity and mealy-mouthed euphemism, depending on context, must be extremely difficult. Within recent decades one outstanding literary work has achieved the exceptional feat of escaping completely from both modern language and mentality to attain total integration into late 18th to early 19th-century society: Patrick O’Brian’s masterly Aubrey-Maturin 20-volume novel sequence.

For film and television directors, however, at the more superficial level of costume, hats remain a key issue. In French classes at school one was taught that, if conversing with a Frenchwoman in the street, one should remove one’s hat (as in Britain) and remain bareheaded until the lady said: “Couvrez-vous, monsieur.” Yet in television dramas, even today and even in a Regency context, men routinely remain firmly covered in the presence of a woman.

It was Lord Fellowes (“Lord Julian Fellowes”, in the untutored usage of broadsheet journalists who entitle him as the son of a duke rather than as a life peer), who, through the medium of Downton Abbey, taught the nation that a servant knocks on a bedroom door, but not on a drawing-room door. His further tuition is still badly needed in many television studios, but probably not on the set of “Howards End”.