This name was borne by the heroine of Lewis Carroll's novels Alice's Adventures in Wonderland (1865) and Through the Looking Glass (1871).
The spelling was later altered to Cordelia when Geoffrey's story was adapted by others, including Edmund Spenser in his poem The Faerie Queene (1590) and Shakespeare in his tragedy King Lear (1606).
As an English name it has been very popular since the Middle Ages. It was the top name for girls in England and Wales in the 1920s, 30s and 40s, but it declined in the latter half of the 20th century.
Other saints by this name include a queen of Scotland and a princess of Hungary. It was also borne by Queen Margaret I of Denmark, who united Denmark, Sweden, and Norway in the 14th century. Famous literary bearers include American writer Margaret Mitchell (1900-1949), the author of Gone with the Wind, and Canadian writer Margaret Atwood (1939-). Others include American anthropologist Margaret Mead (1901-1978) and British prime minister Margaret Thatcher (1925-2013).
The name was common in France during the Middle Ages, and was introduced from there to England, though it eventually became rare. Interest in it was revived by the character Melanie Wilkes from the novel Gone with the Wind (1936) and the subsequent movie adaptation (1939).
As an English name, it became popular due to the Fleetwood Mac song Rhiannon (1976), especially in the United Kingdom and Australia.