Founder of the Abbey Theatre, playwright, folklorist, patron of WB Yeats and chatelaine of Coole Park, Lady Augusta Gregory was a formidable figure.

Privately, however, this powerful woman, who enjoyed two passionate love affairs, was devastated by the discovery that her son Robert had an extra-marital relationship.

"That I should have lived to know my son was a cad!" she declared, before leaving for a lecture tour in America in 1915.

Her shock was so profound that she instructed Robert not to come to the station to see her off.

Such behaviour is one of many hidden contradictions about Lady Gregory, who made Coole Park a home of the Irish Literary Revival and was described by George Bernard Shaw as "the greatest living Irishwoman".

On the surface, she seemed the epitome of an emotionally restrained individual; she had married pragmatically and, after her husband's death, her 40 years of widow's black proclaimed a lack of interest in remarriage.

Yet shortly after her marriage, she fell in love and had a deep relationship with the poet Wilfrid Scawen Blunt, and at the age of 60 enjoyed a liaison with a wealthy American lawyer -- yet when she learned that her adored only son was not just having a relationship with another woman, but that his his wife was being forced to go along with it, she was horrified.

Robert, in fact, was openly sleeping with a mutual friend and had tried to convince his long-suffering wife Margaret to accept the situation.

"Robert was indifferent to her distress," says writer Judith Hill, who has written a biography of Gregory. "He showed little regard for Margaret's feelings and Lady Gregory described him as a cad."

Up to then, while Gregory is believed to have been somewhat disappointed in Robert's lack of achievement -- his art had not, perhaps, caused the sensation she may have wished for -- this was the first time she had been seriously disapproving.

"What we know about his affair comes from Margaret's diary, which was lost to view for many years," explains Hill.

For Gregory, the discovery came as an enormous shock -- she had endured excoriating guilt and self-recrimination over her youthful affair with Wilfrid Blunt early in her marriage.

"She had felt huge guilt towards herself. She felt she had acted wrongly, and that she had somehow failed both herself and the expectations of her upbringing and she was determined to be a good mother and wife and to set herself up to be an exemplary person," says Hill.

As a result, she was horrified by her son's bullying and unprincipled behaviour, which contrasted so strongly with the moral scruples she had felt in similar circumstances.

Her feelings were possibly rooted in her Victorian upbringing, with a moralistic, distant mother Frances, who was addressed as 'Mistress' by her 13 children, and an autocratic and profligate father.

Born Isabella Augusta Persse in March 1852, the daughter of a Galway landowner, the future Lady Gregory was apprised very early on of her insignificance to both her family and the world at large.

Simply being born a girl meant Gregory was a disappointment to her mother.

Her mother's prejudice was expressed in many ways -- fires were lit later in the autumn in the girls' schoolroom, and their education was scantier than the boys'.

Frances was a Church of Ireland evangelical who imposed an intensely religious upbringing on her children and, says Hill, Augusta observed that religious bias often clouded her mother's judgement.

"Her brothers were allowed to do whatever they liked, but the girls were expected to behave. It was a Victorian idea that women would behave and men could get away with things," says Hill, who explains that in those times, girls were often seen as a financial burden.

"Lady Gregory's mother wasn't close to them emotionally. Augusta remembered her mother being very cold and having no real relationship with them.

"Her mother was quite a bigoted, irascible person, the sort of person she would not want to be, though she did internalise a lot of the standards that her mother had set."

Her marriage to William was clearly an escape -- her family simply assumed she would embrace spinsterhood and the role of caring for her brothers.

When she married 60-year-old William in March 1880, Gregory was just 28 and excited by the new life that beckoned. It was her marriage that set her on the road to what was to be a fulfilling life.

William was an important and influential man, a former governor of Ceylon and MP. Well known in aristocratic and artistic circles, he was on first-name terms with luminaries such as Robert Browning and Henry James.

Within a year of the marriage, Gregory was pregnant with their son Robert. While Robert was still a very small baby, the couple travelled to Egypt. It was here that the young wife and mother met the poet and campaigner Wilfrid Blunt and fell head over heels in love.

Although the relationship lasted only a year, the couple remained friends for life. As far as is known, the affair remained a secret, only coming into the public arena when Blunt's archive was opened in the 1970s, revealing the 12 sonnets that she had written to him.

It took her a long time to get over the affair, and it's not certain if William knew or guessed, says Hill.

"William may well have expected it because he was so much older and may have turned a blind eye as long as it was not known about publicly, but we don't know what really went on."

But whatever may have happened, she was utterly riddled with guilt, says Hill: "She didn't do it lightly. She fell in love with Blunt, had an affair with him and was friendly with him for many years. When he was imprisoned many years later during the Land Wars, she wrote him poetry in prison."

Robert became her pride and joy, and after William died in 1892, she dedicated herself to doing the right thing by her son, sending him to Harrow and later to Oxford.

"It was important to her that her son have a proper career, inherit Coole and become an Anglo-Irish gentleman," says Hill.

In September 1906, Robert married Margaret Parry, whom he had met in art school. She too was an artist and the couple enjoyed a semi-bohemian lifestyle. They stayed on at Coole, as did Gregory, who continued to run the estate in an arrangement which left Robert and Margaret quite free.

The couple, who eventually had three children, divided their time between Paris, London and Coole.

In 1911, Gregory embarked on a passionate affair with successful New York lawyer John Quinn, 18 years her junior and a strong supporter of the Irish cultural revival.

When Gregory travelled to America in 1911, she stayed with him. When she arrived home, she wrote him passionate letters.

Eventually, however, she apparently decided that she must not indulge her feelings any longer.

The 1915 affair between Robert and Nora Summers eventually ended. Margaret's diary describes a violent encounter between Robert and Norah's husband, and he enlisted to fight in the First World War, where he was killed in 1918.

Gregory was by then an established playwright and well known in America. There, she had a reputation as a strong independent woman who gave popular lectures.

At home, she failed to save Coole Park, which was sold and the house demolished.

Yet she transcended a clearly unpromising start. "She wasn't expected to marry and her expectations of self-fulfilment were extremely low -- yet her plays were published all over the world and translated into different languages.

In May 1932, she was buried in the Protestant graveyard in Galway, neither a Roxborough Persse nor a Coole Gregory, says Hill, "but a singular spirit surveying the airy blue of the Galway sea and the distant Connemara mountains".

'Lady Gregory; An Irish Life' by Judith Hill, The Collins Press, €14.99.

Judith will give a talk on September 25 at 10.30am at the Lady

Gregory Autumn Gathering,

Coole Park, Galway

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