Image copyright Getty Images

Maud Gonne played a public role in the struggle for Irish independence, but her life also included private tragedy. Her grief over a child who died at the age of two inspired an unpublished poem by W B Yeats - and she was so desperate to reincarnate the boy that she had sex in his tomb.

Actress, activist, feminist, mystic, Maud Gonne was also the muse and inspiration for the poet W B Yeats, who immortalised her in some of his most famous verses.

After the Free State was established in 1922, Maud Gonne remained a vocal figure in Irish politics and civil rights. Born in 1866, she died in Dublin in 1953.

But for many years in her youth and early adulthood, Maud Gonne lived in France.

Of this part of her life, much less is known. There is one long-secret and bizarre episode, however, that has now been established as almost certainly true.

This was the attempt in late 1893 to reincarnate her two-year-old son, through an act of sexual intercourse next to the dead infant's coffin.

I cannot imagine any reason why she would have made the story up - it is too bizarre and too personal Warwick Gould, Yeats scholar

Maud Gonne was English by birth. Her father, Thomas, was a captain in the British army, and during part of her childhood the family lived in Ireland. This was where her interest in Ireland began.

Later Maud was sent to be educated by a governess in France. There was also a rich aunt who introduced her to society in Paris. She was barely out of her teens when her father died, and not long afterward she began a relationship with a right-wing French politician called Lucien Millevoye.

"Millevoye was obviously a replacement father figure," says Yeats scholar Deirdre Toomey. "He was 16 years older than she."

Millevoye was a follower of Gen Georges Boulanger, a hardline nationalist who in the late 1880s briefly looked like he might be the future leader of France.

Boulangistes like Millevoye were obsessed with recapturing the lost eastern territories of Alsace and Lorraine. But Millevoye was also strongly anti-English, and he encouraged Maud Gonne in her own growing hostility to the Crown in Ireland.

Image copyright Library of Congress

Maud had been travelling regularly to Ireland, learning at first hand of the rent strikes and evictions in the countryside. She was increasingly sure her future lay in opposing the English interest in Irish politics.

Then on 30 January 1889, in Bedford Park, London, there took place the famous meeting between Maud Gonne and the young poet William Butler Yeats.

Find out more Listen to From Our Own Correspondent for insight and analysis from BBC journalists, correspondents and writers from around the world Broadcast on Radio 4 on Saturdays at 11:30 and Thursdays at 11:02 GMT and BBC World Service Listen to the programme Download the programme

Yeats was immediately overwhelmed. According to his biographer R F Foster, Maud Gonne appeared to Yeats "majestic, unearthly… Immensely tall, bronze-haired, with a strong profile and beautiful skin, she was a fin-de-siecle beauty in Valkyrie mode".

It was the start of a mutually obsessive relationship that would last half a century. But what Yeats did not discover until very much later was that less than three weeks before this momentous first encounter, Maud Gonne had given birth to a baby boy.

The baby was called Georges, he was born in Paris, and he was Lucien Millevoye's.

Gonne - a complicated character if ever there was one - initially kept Georges' existence secret from Yeats. When he did find out about the baby, she insisted that he was not hers but adopted.

"It is surprising how naive Yeats seems to have been over Gonne's child," Toomey says. "He must have wanted to believe that what she said was true about it not being hers."

But two-and-a-half years later Georges was dead. It is not certain how he died, but it was probably meningitis.

When Yeats met Gonne next, it was in Dublin in October 1891 and she was shattered. By a strange twist, she arrived in Kingstown (now Dun Laoghaire) on the same mail boat that brought the body of the just-dead Irish politician-cum-hero Charles Parnell.

People thought her tears were for Parnell, but they were for Georges.

Over the next two years, in Dublin, London and Paris, a grief-stricken Gonne was drawn into the occultist and spiritualist worlds that were already of deep importance to Yeats.

Writing many years later in his memoirs, Yeats recalled that Gonne repeatedly asked his circle of friends about the reality of reincarnation. One friend - the writer and mystic George Russell - assured her that it was indeed possible to recreate a dead child's soul if the parents went about it in the right way.

And so the story leads to a white stone mausoleum in the cemetery of the small riverside town of Samois-sur-Seine, 50km (30 miles) south-east of Paris.

Image copyright ALAMY

Maud Gonne used to rent a house here, to get away from the bustle of Paris and when Georges died, she had him interred in the town's graveyard.

Having inherited a large sum of money on the death of her father, she paid for a memorial chapel - the biggest in the cemetery. In a crypt beneath, the child's coffin was laid.

In late 1893 Gonne re-contacted Lucien Millevoye, from whom she had separated after Georges' death.

She asked him to meet her in Samois-sur-Seine. First the couple entered the small chapel, then opened the metal doors leading down to the crypt.

They descended the small metal ladder - just five or six steps. And then - next to the dead baby's coffin - they had sexual intercourse.

Media playback is unsupported on your device Media caption Hugh Schofield visits the mausoleum where Georges was laid to rest

How do we know this?

The evidence comes from Yeats. In his posthumous memoirs - not published till 1972 - he wrote that Gonne herself told him the story.

"Gonne and Yeats were always extremely close," says Yeats scholar Warwick Gould.

"And I cannot imagine any reason why she would have made the story up. It is too bizarre and too personal. But it accords with what we know of her interest in reincarnation."

On a Child's Death

In 1893 Yeats wrote a poem that was never published. It is called On a Child's Death, and it is clearly inspired by Maud Gonne's dead son, and her consequent grief - though when he wrote it Yeats still thought Georges was adopted. Scholars say it is of uneven quality, which is why Yeats did not want it to be part of his canon.

You shadowy armies of the dead

Why did you take the starlike head

The faltering feet, the little hand?

For purple kings are in your band

And there the hearts of poets beat;

Why did you take the faltering feet?

She had much need of some fair thing

To make love spread his quiet wing

Above the tumult of her days

And shut out foolish blame & praise.

She has her squirrel & her birds

But these have no sweet human words

And cannot call her by her name:

Their love is but a woodland flames

You wealthy armies of the dead

Why did you take the starlike head.

On A Child's Death was reproduced with the permission of Caitriona Yeats

The purpose of the act was to recreate the baby's soul in the new baby that she would conceive with the same father. By having sex next to the corpse, it was hoped that the process of metempsychosis - the transmigration of the soul - would be made easier.

Whether the soul of Georges transmigrated is a matter for metaphysicians. What is certain is that in August 1894 Maud Gonne had another baby.

This was her daughter Iseult. Maud Gonne brought up the child as her own, but their relationship was always odd. Later she refused to call her "daughter" in company, instead describing her as a "kinswoman" or "cousin".

As an adult Iseult had an affair with Ezra Pound and married the controversial Irish-Australian novelist (and Nazi sympathizer) Francis Stuart. She died a year after her mother, in 1954.

Maud Gonne, meanwhile, converted to Catholicism (much to Yeats' dismay) and in 1903 married the Irish soldier and Republican, John MacBride.

With him she had her third child, who grew up to be the Irish politician, IRA leader, international statesman and Nobel peace prize winner Sean MacBride.

John MacBride was shot by the English in the Easter Rising of 1916. Sean MacBride lived until 1988.

The Gonne mausoleum in Samois-sur-Seine was long forgotten. Few knew the story of Maud Gonne's dead baby - almost no-one knew the story of the secret sex.

Occasionally Yeats scholars would come to pay a visit out of curiosity. But in the town - once the generations had moved on - they had never heard of Maud Gonne.

Interest in the cemetery resided solely in its other famous occupant - the jazz guitarist Django Reinhardt.

Image copyright ALAMY Image caption A plaque commemorating guitarist and composer Django Reinhardt who lived and died in Samois-sur-Seine

Today though, there is a small resurgence of interest. Intrigued by the mausoleum, local councillor Josette Dufour conducted her own research and has now written a short monograph on the Georges Gonne story.

The mausoleum no longer belongs to the Gonne family. Though the plot was bought by Gonne "in perpetuity", in practice the freehold had to be renewed - and it wasn't.

But inside the Grecian-style edifice, there are still the metal doors in the ground.

Josette Dufour provided a key for the padlock. And there in the crypt, on a small trestle - lies the coffin of baby Georges. It is in fact a double-coffin, because for transport from Paris the law stated that the original coffin had to be encased in another.

On the lid are some crumbling flowers made of papier-mache or some other material. And a plaque bears his name: Georges Gonne. Born January 11 1889. Died August 31 1891.

When she died in 1953, Maud Gonne's will bore no reference to Iseult.

But she asked to be buried with Georges' baby-shoes in her coffin.

How to listen to From Our Own Correspondent:

BBC Radio 4: Saturdays at 11:30 and Thursdays at 11:02 GMT

Listen online or download the podcast.

BBC World Service: At weekends - see World Service programme schedule.

Subscribe to the BBC News Magazine's email newsletter to get articles sent to your inbox.