It seems a curious irony that the unwritten rule permitting only black actors to play Othello appears to have led now – despite an acting profession characterised by its ethnic diversity – to a War of the Roses in which all 22 of the actors are white.

I refer to the production taking to the stage at the Rose Theatre in Kingston-upon-Thames on Wednesday, September 16.

It is directed by Trevor Nunn and features a cast led by Joely Richardson and Rufus Hound.

The actors’ union equity has accused Sir Nunn of “whitewashing history” and “locking minorities out of the cultural picture”.

He has responded by saying he made an artist decision over the matter, with casting according to “historical verisimilitude”.

He claimed: “The connection between the characters, and hence the narrative of the plays, are extremely complex, and so everything possible must be done to clarify for an audience who is related by birth to whom.”

It is my contention that such action could not have been taken were not the strict principle of ‘colour-blind casting’ so routinely broken over Othello.

Mr Nunn has urged in his defence he was involved from the early 1970s in the movement to cast without reference to colour, and this is certainly true.

In his 1983 Royal Shakespeare Company production of the Henry IV plays, the role of Hotspur was given to Oxford-educated Hugh Quarshie.

Seventeen years later the actor made clear he thought it no issue when David Oyelowo, with a family background in Nigeria, became Stratford’s first black king, Henry VI, in the three plays which make up the War of the Roses.

“This is not a defining moment for black actors,” he said. “It is a lot easier to have non-traditional casting with Shakespeare.”

Though not, as I said, with Othello; Mr Quarshie was RSC’s this year.