GETTY Wallis Simpson, left, and the Queen Mother feuded for many years

It is said that during the abdication crisis in the 1930s he went down on his knees and prayed in vain that he would be spared the burden of becoming head of state. His wife Elizabeth, mother of our current Queen, shared his fears that he was terribly unprepared. She was always convinced that George’s life was shortened by the stress caused by stepping in for his older brother Edward VIII, who gave up the throne for an American divorcee. And Elizabeth never forgave Wallis Simpson, the woman she blamed for sentencing her to decades of widowhood. Their enduring feud is the subject of a new BBC Two drama-documentary later this week. Royal Wives At War, starring Gina McKee as Wallis and Emma Davies as the Queen Mother, looks at events through the eyes of the two women. The programme, said to be inspired by real events and letters, also deals with the claim that the Queen Mother’s ire was also fuelled by jealousy. It is alleged that she was secretly in love with the dashing Edward and was furious with her rival for stealing him away. The abdication was the biggest constitutional crisis in modern Royal history.

GETTY The Queen Mother passed away on 29 October 2004, aged 102

Edward’s insistence on marrying a divorcee for love, over duty, meant he was never crowned and reigned for just 325 days. Edward had a reputation as a playboy and there had been several affairs with married women while he was Prince of Wales. None caused more scandal than his relationship with Mrs Simpson, as it became obvious that the couple had fallen in love. Elizabeth, the daughter of a Scottish earl, and Wallis, whose father was a wealthy Baltimore flour merchant, moved in the same social circles and were just four years apart in age. But personality and style-wise they were complete opposites and loathed one another from their first meeting. Wallis, the thin and chic American socialite who favoured dark colours, was always cast as the wicked witch against Elizabeth, the English rose who dressed in pastels and had a strict sense of decorum. There was one disastrous encounter, in 1935, at Edward’s country retreat Fort Belvedere in Windsor Great Park. Elizabeth is said to have walked into a room to discover Wallis doing an imitation of her. Wallis dubbed Elizabeth “the Dowdy Duchess” or “the fat Scottish cook”, while the future Queen simply called the American “that woman” or “a certain person”.

BBC The feud is the subject of a new BBC drama, Royal Wives At War, showing on Friday, BBC2 at 9pm

In one letter Elizabeth stated that she regarded Wallis as “the lowest of the low, a thoroughly immoral woman”, who she tried her best to avoid. She is also said to have described “the sheer vulgarity” of Edward and Mrs Simpson. “I do not feel I can ask her to the house,” she once wrote to her mother-in-law, Queen Mary. “This fact is bound to make relations a little difficult.” Their mutual antipathy hardened into distrust and lasting resentment as the abdication crisis unfolded, following the death of King George V in January 1936. Elizabeth admitted that she felt “quite overcome with horror and emotion” when it became obvious that Edward could not be dissuaded from marrying Wallis. She regarded her brother-in-law as a weak man who had been led astray by a manipulative femme fatale. Forced to choose between the crown and Wallis, Edward opted for the latter and abdicated. “I now quit altogether public affairs,” he announced in a sombre farewell broadcast from Windsor Castle. Edward, then aged 42, went into exile in France, where he married Wallis in 1937 and was given the title Duke of Windsor.

GETTY Elizabeth refused to name Simpson, simply calling the American “that woman”

Suddenly Albert, was thrown into the spotlight. He was crowned George VI on May 12, 1937, with his wife the former Elizabeth Bowes-Lyon at his side. Pointedly, Edward and Wallis were not on the guest list and chose the eve of the coronation to announce their formal engagement. George VI, who was 41 when he became King, was conscientious and worked diligently to adapt to the unexpected role. But he was a nervous man, who spoke with a stutter, and from the start he found ruling the nation a struggle. His wife could not help but notice the toll it took on her beloved Bertie. Shortly after he was crowned it was remarked to her that his brother Edward, now shorn of responsibility, no longer had bags of exhaustion under his eyes. “Yes,” she replied bitterly. “Who has the lines under his eyes now?” Although Wallis became Duchess of Windsor she was refused the title Royal Highness, a snub that is said to have been approved by Elizabeth and enraged Edward. Elizabeth was also deeply unimpressed by the Duke and Duchess of Windsor cosying up to the Nazis before the Second World War. She is once said to have remarked: “The two people who have caused me the most trouble in my life are Wallis Simpson and Hitler.”

The Queen Mother in pictures Wed, March 29, 2017 Lady Elizabeth Bowes-Lyon, better known as the Queen Mother in pictures. Play slideshow Getty 1 of 36 The Queen Mother (4 August 1900 – 30 March 2002)

GETTY The Queen Mother tried multiple times to dissuade Edward from marrying Wallis

Many official papers relating to Elizabeth’s role in the crisis will remain secret until 2037 and historians disagree about the depth of the feud. When King George VI died aged 56 in 1952 his brother flew in alone from France for the funeral. Neither Edward nor Wallis was invited to the present Queen’s coronation the following year. The Duchess of Windsor did stay at Buckingham Palace in 1972, after Edward died and was buried at Windsor. However, she only met the Queen Mother on the day of the service and there’s no record of what words were exchanged. When the Duchess of Windsor died in 1987 the Queen Mother attended her funeral service, also at St George’s chapel, Windsor, but not her burial. However, it was later discovered that she had been sending her Christmas cards, including a cordial personal message, since the Duke’s death in 1972. Elizabeth refused to speak publicly about the abdication or her feelings for the Duchess of Windsor. “I’m afraid I just can’t talk about it,” she told the broadcaster Ludovic Kennedy, who once dared to raise the issue.

GETTY Edward VIII and Wallis Simpson on their wedding day in 1936 near Tours, France