Beckford was born on 29 September 1760 in the family's London home at 22 Soho Square. At the age of ten, he inherited a fortune from his father William Beckford, who had been twice a Lord Mayor of London, consisting of £1 million in cash (£125 million as of 2015), an estate at Fonthill in Wiltshire (including the Palladian mansion Fonthill Splendens), and several sugar plantations in Jamaica, worked by enslaved Africans. This fortune allowed him to indulge his interest in art and architecture, as well as writing. He was briefly trained in music by Wolfgang Amadeus Mozart, but his drawing master, Alexander Cozens, was a greater influence, and Beckford continued to correspond with him for some years until they fell out.
On 5 May 1783 Beckford married Lady Margaret Gordon, a daughter of the fourth Earl of Aboyne. However, he was bisexual and after 1784 chose self-exile from British society when his letters to William Courtenay, later 9th Earl of Devon, were intercepted by the boy's uncle, who advertised the affair in the newspapers. Courtenay was just ten years old on first meeting Beckford, who was eight years older.
For many years Beckford was believed to have conducted a simultaneous affair with his cousin Peter's wife Louisa Pitt (c.1755–1791). Beckford was discovered (according to a house guest at the time) to be "whipping Courtenay in some posture or another" after finding a letter penned by Courtenay to another lover. Although Beckford was never punished for child molestation, fornication, or attempted buggery, he subsequently chose self-exile to the continent in the company of his long-suffering wife (who died in childbirth aged 24).
William Beckford's Grand Tour
through Europe, shown in red
Having studied under Sir William Chambers and Cozens, Beckford journeyed in Italy in 1782 and promptly wrote a book about his travels: Dreams, Waking Thoughts and Incidents (1783). Shortly after this came his best-known work, the Gothic novel Vathek (1786), written originally in French; he boasted that it took a single sitting of three days and two nights, though there is reason to believe that this was a flight of his imagination.
His other principal writings were Memoirs of Extraordinary Painters (1780), a satirical work; and Letters from Italy with Sketches of Spain and Portugal (1834), full of brilliant descriptions of scenes and manners. In 1793 he visited Portugal, where he settled for a while.
Beckford's fame, however, rests as much upon his eccentric extravagances as a builder and collector as upon his literary efforts. In undertaking his buildings he managed to dissipate his fortune, which was estimated by his contemporaries to give him an income of £100,000 a year. The loss of one of his Jamaican sugar plantations to James Beckford Wildman was particularly costly. Only £80,000 of his capital remained at his death.