Oxenhall, Newent GL18, Regno Unito
Theodosia Blacker, Lady Monson (23 July 1803, Warkworth, Northumberland - 3 July 1891, Malvern Wells, Worcerstershire) was a promoter of women's rights, horsewoman, atheist and landscape painter. According to Sharon Marcus, she was the last companion of Matilda Hays.
Theodosia Blacker, Lady Monson was born on 23 July 1803 at Warkworth, Northumberland, the fifth and youngest daughter of Maj Latham Blacker (1765-1846) of Drogheda, Ireland, and subsequently of Newent, Gloucestershire, and Catherine Maddison (1769-1823). Her paternal grandparents were Latham Blacker (c. 1711 - post 1765) and Martha Beaver (died 1802). Her maternal grandfather was Col George Maddison of Lincolnshire. She had one sister, Catherine Blacker Onslow.
She married Frederick John Monson, 5th Baron Monson (1809–1841) on 21 June 1832 at St James, Westminster, London, but lived with him for less than a week..
She was a friend of Anna Jameson and the Brownings, Elizabeth Barrett Browning and Robert Browning.
Lady Monson was the last companion of Matilda Hays (1820–1897), a 19th-century English writer, journalist and part-time actress.
In December 1859, Lady Monson rented 19 Langham Place as a homeplace for the English Woman's Journal and furnished at her own expenses new offices. The place had also a committee room, a reading room and a coffee shop open from 11am to 10pm. In 1860 it became "The Ladies Institute" managed by Sarah Lewin (1812-1898), a circle of like-minded women known as Langham Place group who gathered there. Members included Helen Blackburn, Matilda Hays, Emily Faithfull, Maria Rye, Emily Davies, Jessie Boucherett and Lady Monson herself. At the end of 1863, Lady Monson refitted the place to be an house.
She died on 3 July 1891 at Malvern Wells, Worcerstershire.