Louisa Stuart Costello (9 October 1799 – 24 April 1870) was an Anglo-Irish author on travel and French history, said to have been born either in Ireland[1][2][3] or Sussex.

She and her brother Dudley Costello, also well known for travel writing, promoted the copying of illuminated manuscripts.

[1] By the age of 15 she had become a proficient artist and later her earnings from miniature painting were enough to support her mother and to keep her brother while he attended Sandhurst.

[5] She wrote over 100 texts, articles, poems and songs, and knew such people as Sir Walter Scott, Charles Dickens, Lord Byron, Thomas Moore.

The Maid of the Cyprus Isle (1815) was among many books of travel, which were very popular, as were her novels, which drew chiefly on French history.