Eton College, Windsor SL4 6DW, Regno Unito
Beaudesert House, Longdon, Rugeley WS15 4LN, Regno Unito
Plas Newydd, Llanfairpwllgwyngyll LL61 6DQ, Regno Unito
St Edwen, Llanfairpwllgwyngyll LL61 6EZ, Regno Unito
Henry Cyril Paget, 5th Marquess of Anglesey Bt, (16 June 1875 – 14 March 1905), styled Lord Paget until 1880 and Earl of Uxbridge between 1880 and 1898, and nicknamed "Toppy", was a British peer who was notable during his short life for squandering his inheritance on a lavish social life and accumulating massive debts. Regarded as the "black sheep" of the family, he was dubbed "the dancing marquess" for his habit of performing "sinuous, sexy, snake-like dances" and for his Butterfly Dancing, taken from Loie Fuller where a voluminous robe of transparent white silk would be waved like wings. 
The Complete Peerage says that he "seems only to have existed for the purpose of giving a melancholy and unneeded illustration of the truth that a man with the finest prospects, may, by the wildest folly and extravagance, as Sir Thomas Browne says, 'foully miscarry in the advantage of humanity, play away an uniterable life, and have lived in vain.'"
Paget was the eldest son of the 4th Marquess by his father's second wife, Blanche Mary Boyd. However, rumours persisted that his biological father was the French actor Benoît-Constant Coquelin, a rumour that gained some currency when, according to some sources, after the death of his mother in 1877, when he was two years old, Paget reportedly was raised by Coquelin's sister-in-law in Paris until he was eight. That story seems to have been a confusion of facts. The sister-in-law, née Edith Marion Boyd, was the fourth marquess's aunt, one of his mother's sisters, and she did not wed Coquelin's brother Gustave until 1891. His stepmother from 1880 was an American, Mary "Minna" Livingston King, the widow of the Hon. Henry Wodehouse.
He attended Eton College, later receiving private tuition, and was commissioned as a Lieutenant in the 2nd Volunteer Battalion of the Royal Welsh Fusiliers. On 20 January 1898 he married his cousin Lilian Florence Maud Chetwynd (1876–1962). Upon the death of his father on 13 October 1898, he inherited his title and the family estates with about 30,000 acres (120 km²) in Staffordshire, Dorset, Anglesey and Derbyshire, providing an annual income of £110,000 (equivalent to £11 million per year in 2018).
Paget swiftly acquired a reputation for a lavish and spendthrift manner of living. He used his money to buy jewellery and furs, and to throw extravagant parties and flamboyant theatrical performances. He renamed the family's country seat Plas Newydd as "Anglesey Castle" and converted the chapel there into a 150-seat theatre, named the Gaiety Theatre. Here he took the lead role, opulently costumed, in productions ranging from pantomime and comedy to performances of Oscar Wilde's An Ideal Husband and Shakespeare's Henry V. Early performances from around 1899 were mostly variety performances of song and dance numbers, sketches and tableaux vivants in front of an invited audience of notable local people. In 1901, the Gaiety Theatre was refurbished and fitted out with electric stage lighting and re-opened as a public entertainment venue.
For three years Paget took his theatre company on tour around Britain and Europe. His wife disapproved of his lifestyle and obtained a decree nisi of divorce on 7 November 1900; the marriage was later annulled due to nonconsummation, according to Lady Anglesey's grandson by her second marriage, the historian Christopher Simon Sykes. The breakdown of his marriage effectively gave Paget more freedom to enjoy his self-indulgent lifestyle. By this stage he had already begun to mortgage his estates to raise money.
On 10 September 1901, Paget's French valet Julian Gault took the opportunity of his employer's absence at the theatre to steal jewellery to the value of £50,000. At the time, Paget was living in the Walsingham House Hotel in London. Gault, who was later arrested at Dover, testified in court that he had been instructed to steal the jewels by a French woman of his acquaintance called Mathilde (who had taken the jewels to France and was never found). Although Gault's testimony was believed to be true, he pleaded guilty at the Old Bailey on 22 October and was sentenced to five years' imprisonment.
Paget's outrageous and flamboyant lifestyle, his taste for cross-dressing, and the breakdown of his marriage, have led many to assume that he was gay. Writing in 1970, the homosexual reformer H. Montgomery Hyde characterised him as "[t]he most notorious aristocratic homosexual at this period". One journalist wrote, “I am driven to the conclusion from much that I have seen that there are men who ought to have been born women, and women who ought to have been born men … Bearing the form of a man, he yet had all the tastes, something even of the appearance, of not only a woman, but, if the phrase be permissible, a very effeminate woman.”  There is no evidence for or against his having had any lovers of either sex: performance historian Viv Gardner believes rather that he was "a classic narcissist: the only person he could love and make love to was himself, because, for whatever reason, he was 'unlovable'". The deliberate destruction by his family of those of his papers that might have settled this matter has left any assessment speculative. However, it would appear that he did not have sexual relations with his wife, who initially left him after just six weeks: "The closest the marriage ever came to consummation was that he would make her pose naked covered top to bottom in jewels and she had to sleep wearing the jewels."
By 1904, despite his inheritance and income, Paget had accumulated debts of £544,000 (£50 million in 2018) and on 11 June was declared bankrupt. His lavish wardrobe, particularly his dressing gowns from Charvet, and jewels were sold to pay creditors, the jewels alone realising £80,000.
In 1905, Paget died in Monte Carlo following a long illness, with his ex-wife by his side, and his remains were returned to St Edwen's Church, Llanedwen, for burial. The Times reported that despite all that was known of him, he remained much liked by the people of Bangor, who were sorry to hear of his death. Lilian, Marchioness of Anglesey, married, in 1909, John Francis Grey Gilliat, a banker, by whom she had three children.
The title passed to his cousin Charles Henry Alexander Paget, who destroyed all the papers of the 5th Marquess and converted the Gaiety Theatre back into a chapel. It was at least in part owing to the debts left by the 5th Marquess that the family's principal English estate at Beaudesert, Staffordshire, had to be broken up and sold in the 1930s.