Born into poverty in the Wirral in 1765, Emma was the daughter of a blacksmith. She made her way to London at the age of 12 and, ambitious to a fault, she was drawn to Covent Garden where high culture and fashionable celebrity met a grimy underworld of sexual exploitation.

Emma became the lover of a young nobleman, but was rejected by him when – aged 16 – she became pregnant.

The future looked bleak until a new protector, Charles Greville, made provision for the child and introduced Emma to the artist George Romney.

With her innate theatricality and good looks, Emma found fame while still in her teens as Romney’s muse. During hundreds of sittings he completed dozens of canvases. Many artists would follow in his footsteps making Emma one of the most painted women in British history.

Fede or betrothal ring, 1800-05, one of a pair that the lovers exchanged because they could not marry

Greville, however, longed for a wife, and Emma was a hindrance. A solution came in the form of his uncle – Sir William Hamilton, the British envoy in Naples. Unknown to Emma, Greville convinced Hamilton to take her on as his own mistress. Emma was sent to Naples, expecting Greville to join her. When the truth became clear, she was crushed.

Determined to make the best of her circumstances, she threw herself into educational opportunities made available to her by Sir William.

She used her experience of modelling for Romney to create her own unique performance art: the “attitudes”; bringing to life the paintings and sculptures that enraptured the Grand Tourists in Naples.

Her poses and elegant use of costume and shawls became the must-see spectacle, winning the admiration of an elite audience that were all too ready to criticise a girl of Emma’s humble origins.

Horatio Nelson, Vice Admiral of the White by Johann Heinrich Schmidt

When she married the 61-year-old Sir William in 1791, Emma, 26, made a leap up the social ladder.

As the wife of an envoy, Lady Hamilton had a role to play in the Neapolitan Court becaming the favourite of Maria Carolina, Queen of Naples and Sicily.

In 1798, following a victory at the Battle of the Nile, Admiral Nelson arrived in Naples. Emma organised lavish celebrations in his honour.

Later, with French forces approaching the city, Nelson arranged for the royal family to be taken on board his flagship and evacuated to Sicily. Emma played a pivotal role on the journey; even cradling Maria Carolina’s dying son in her arms.

■ Emma, Lady Hamilton, by Johann Heinrich Schmidt

Emma and Nelson’s admiration turned to passion, and one of history’s greatest love affairs began. With her lover and her husband Emma travelled back to Britain.

However, Emma’s adulterous relationship with the nation’s hero risked the social status she had struggled so long to possess. Rumours about their infidelity began to circulate back in England, where Nelson’s wife, Frances, awaited. By now, Emma was also pregnant with Nelson’s child.

Emma and Nelson dreamed of happiness, but the realities of life were more complex. Their daughter Horatia was born in secrecy and Emma could not admit to being her mother.

Emma found a country house, Merton Place, which she refurbished as her home with Nelson. But Nelson’s duties kept him away at sea for years at a time and his death at Trafalgar shattered Emma’s world. She was heartbroken, and never recovered. The famous uniform coat that he wore during the battle was arranged on her bed next to her grief-stricken form.

'Scared History' By Mrs Trimmer - Hand written note in the front cover to Nelson from Emma Hamilton

Without youthful beauty or the security of marriage, Emma’s fortunes never recovered either. Her life became increasingly difficult, made worse by her own desperate and extravagant efforts to maintain her lifestyle.

In 1813 she was arrested for debt and sent to King’s Bench Prison. After her release she spent her final months of failing health far from her creditors in Calais. She died in January 1815, broken and destitute.

At every point of Emma’s journey, this dazzling woman fought through the barriers and conventions of a man’s world that she could never completely control.

Emma Hamilton: Seduction And Celebrity at the National Maritime Museum, Greenwich , Until April 2017, National Maritime Museum, Greenwich, November 3, 2016–April 17 2017, Adult £14, Child £7, Concession £6