Lady Diana Spencer was born in 1735, the eldest child of the third Duke of Marlborough. She was expected to follow a traditional path through life: educated in the fashion considered suitable for a girl, and married to a man of the appropriate rank for a duke's daughter. However, Lady Di overturned convention. She left her husband, pursued a secret relationship with Topham Beauclerk, hid the birth of an illegitimate child, was divorced, remarried and eventually had to earn her living by painting.
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Her designs were used by Wedgwood.
The Museum of London holds a 1797 large sculptural frieze, known as the Pelican figures, that used to be high up on the facade of an insurance building in Lombard Street. This was designed by Lady Diana.
There is a book about this lady : Improper Pursuits: The Scandalous Life of Lady Di Beauclerk, Author: Carola Hicks.