Audrey Etheldreda Townshend, Viscountess Townshend (née Harrison; 1708 – 5 March 1788), was a celebrated English socialite, widely believed to have inspired the character "Lady Bellaston", the notorious fictional seductress in Henry Fielding's The History of Tom Jones, a Foundling.

"Etheldreda" Harrison was born in 1708 to colonial administrator Edward Harrison and heiress Frances (née Bray). She was born at Balls Park in Hertfordshire, the home of her paternal grandparents, Richard and Audrey Harrison, who had 8 sons and 6 daughters, some of whom were likely resident at the family home as she grew up. Shortly after she was born, Etheldreda's father left home to travel the world, trading with China as a sea captain. He was appointed governor of Fort St George in Madras between 1711 and 1717, returning home in 1717 with a fortune, giving him the financial capacity to be returned as a member of parliament for Weymouth and Melcombe Regis and to completely refurbish the house and grounds of Balls Park.

The young Etheldreda was the only surviving heir to her father's fortune and estates, which made her an excellent match for social preferment. Young, beautiful and vivacious, she was probably over indulged by her family and was eager to escape the confines of Balls Park and explore a wider romantic world. Her father used his position to find a good match and at the age of 15 in 1723, she was married to Lord Lynn, a title hastily conferred on Charles Townshend in lieu of his inheriting his father's Viscountcy.

Newlyweds Lord and Lady Lynn moved into the Townshend family home at Raynham Hall in Norfolk as guests of Etheldreda's father-in-law Charles Viscount Townshend and his wife Dorothy née Walpole. Lord and Lady Lynn immediately started a family with their first child born in 1724 (George), the second in 1725 (Charles) and a third around 1726 (Edward). Raynham Hall had become afflicted with smallpox, which is thought to have resulted in the death of Lady Dorothy in 1726 and the Lynn's youngest son Edward in 1731. Etheldreda disliked Norfolk and, at the age of eighteen, looked for opportunities to see and be seen in wider society. In 1731, their fourth son Roger was born, followed by a daughter (Audrey). Reportedly, relationships between Lord and Lady Lynn had always been stormy, dining separately, leading separate lives. Lord Lynn had been having an affair with his housemaid, who became his mistress, which was evidently tolerated by the Townshend family on condition that knowledge of the relationship remained within the family at Raynham. Etheldreda, who had formed a dislike for the Townshends, had other ideas.

Lady Lynn's father died in 1738, leaving her a substantial independent income worth £2000 a year. She began making frequent visits to London, acquiring the lease to a grand house within the precincts of the Palace of Whitehall in the Privy Gardens, where she was to live in opulent style for the rest of her life. Lord and Lady Lynn remained outwardly together with their children at Raynham Hall, but when the old Viscount died in 1738, Lady Lynn became Viscountess Townshend. The new Lady Townshend immediately made the family rift public. At a time when London was suffering from disease and Lady Townshend was consulted on potential cures, she declared that "the greatest number have found relief from the sudden deaths of their husbands". The new Viscount Townshend remained at Raynham with his mistress but his Lady Townshend left for a fast life in London, where she commissioned French artist van Loo to make several half portraits of herself (at the age of 30, illustrated above), publishing woodcut prints entitled Mrs Townshend. A formal separation was agreed three years later in May 1741.

Lady Townshend had the means and the freedom to host whist salons, mount huge Masquerade balls with lavish hospitality at the Privy Gardens, receiving all that was fashionable and select in society of the day, which became renowned throughout the country. Her extravagant life-style played out in public throughout the 1740s when Henry Fielding was writing his The History of Tom Jones, a Foundling, published in 1749, followed by another parody as Lady Tempest in Francis Coventry's The History of Pompey the Little two years later.

Lady Townshend was best known for her public affairs. Her closest intimates reportedly included Prince William, Duke of Cumberland (the son of King George), Thomas Winnington, sir Harry Nesbit, the youthful Lord Frederick Campbell, Henry Fox, 1st Baron Holland, Lord Baltimore, the Duke of Newcastle, Sir Charles Hanbury Williams, both the Sir Thomas Robinsons (Grantham and her landlord) plus various members of the Hervey family of all ages and was sought out by lovers and macaroni of the day, like Casanova and Chevalier d'Éon.

A celebrated wit of her day, Lady Townshend frequently jousted with her closest friends Horace Walpole, George Montagu and Lady Mary Wortley Montagu and George Selwyn, in the golden age of satire in England, as well as more serious commentators like Elizabeth Montagu, Hester Chapone and Mary Delany. As a notable public figure, if you weren't being talked about, lampooned, imitated or even ridiculed, you were not worthy of public attention. Lady Townshend courted controversy. She set herself up as an anti-establishment figure, outwardly opposed to the Hanoverian Court, projecting herself as a Jacobite, opposed to the Government of the day under Sir Robert Walpole, Henry Pelham and Government in general, wielding political influence where she could. A notorious libertine, she alternately espoused the Church of England, Methodism and Catholicism at different times. When George Whitefield was conducting the methodist revival with Lady Townshend in attendance, she was asked "Pray Madam, is it true that Whitfield has recanted" to which she replied "No, Sir, he has only canted".