This was the name of a 13th-century Italian saint who made clothes for the poor. As an English name, it has never been common.
In England, Sarah came into use after the Protestant Reformation. It was consistently popular in the 20th century throughout the English-speaking world, reaching the top of the charts for England and Wales in the 1970s and 80s.
Notable bearers include Sarah Churchill (1660-1744), an influential British duchess and a close friend of Queen Anne, and the French actress Sarah Bernhardt (1844-1923).
This name was common in Sweden and Denmark in the 1970s [1]. It rose in popularity in the English-speaking world in the 1990s, entering the top ten for girls in the United States in 2009. It was also popular in many other countries at that time. Famous bearers include American actress Mia Farrow (1945-) and American soccer player Mia Hamm (1972-), birth names Maria and Mariel respectively.
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).
In Greek legend Clytemnestra was the wife of Agamemnon and the mother of Orestes and Electra. While her husband was away during the Trojan War she took a lover, and upon his return she had Agamemnon murdered. She was subsequently killed by her son Orestes.
Due to the popularity of the saint, the name became common in the Christian world during the Middle Ages. The Normans brought it to England, where it was commonly spelled Cecily — the Latinate form Cecilia came into use in the 18th century.