The codpieces used in the hit BBC drama Wolf Hall were too small and should have been double the size, according to an expert.

This is one of a number of inaccuracy spotted in the big budget adaptation of Hilary Mantel's books and was said to have been done so as not to offend and baffle the shows American audience.

Victoria Miller, who has researched the codpiece for her PHD, said those used in the show would have been far too modest for Henry VIII's court.

Damien Lewis, pictured left, with a small and modest codpiece, and a Renaissance portrait, right, with a much more noticeable and prominent garment

Homeland star Damian Lewis played Henry VIII in the six-part series on the rapid rise to power of Sir Thomas Cromwell in King Henry's court

'They're way too small to be accurate – they should be at least double the size,' said the Cambridge academic, according to the Guardian.

'You can kind of see them there, but they aren't really stuffed, and are easily missed – they've really toned them down for a mainstream audience.

'The codpiece was meant to draw the eye to the general region.'

Mark Rylance, who played Thomas Cromwell, blamed there diminutive size on a 'directive from our American producers'.

'I wasn't personally disappointed by the codpieces: I'm a little more used to them than other people from being at the Globe for ten years,' Rylance said, according to the Daily Telegraph.

'But I can see for modern audiences, perhaps more in America, they may not know exactly what's going on down there.'

In the time of Henry VIII the codpiece was a fashion accessory, which was said to be a symbol of a Tudor man's 'virility'.

Damian Lewis, who played Henry VIII, admitted that the codpieces were a source of some 'giggling' during filming.

This is not the first time that the show has come under fire for historical errors.

When it first aired, historians criticised the decision to cast Kate Phillips as Henry VIII's third wife Jayne Seymour because she was too pretty.

Seymour seen in a portrait by Tudor artist Hans Holbein, is depicted with a noticeably large forehead, double chin, and thin pursed lips.

According to Lucy Worsley, 41, chief curator at Historic Royal Palaces, Miss Phillips, 25, has features which are too dainty.

Miss Worsley said: 'She's too pretty. I did challenge Peter Kosminsky [the director] about that. He laughed and said, "I picked her because of her acting, not because of her forehead".'

Historians also pointed out that Montacute House in Somerset, which was used to portray Greenwich Palace, is from the Elizabethan period.

Historian Lucy Worsley has said that Kate Phillips, pictured left, who plays Henry VIII's wife Jane Seymour, portrait pictured right, in BBC drama Wolf Hall is too pretty

Miss Worsley has previously questioned the authenticity of some aspects of the programme, claiming both the original books and now this adaptation have brought the characters firmly into the modern day.

She said: 'What Hilary Mantel has done is made these characters people for our times, which is interesting for a historian to watch. They are immensely modern, they won't be saying thee and thou and being all dramatic and over the top.

'I think it will make people think the Tudors were just like us in many ways. That's a massive historical question, in some ways they were and in some ways they weren't.'

The programme-makers have revealed the lengths they have gone to to ensure historical accuracy – including an unexpected insistence on straight, white teeth and pristine linen.