This name was known among the Normans due to the Welsh bishop Saint Samson, who founded monasteries in Brittany and Normandy in the 6th century. In his case, the name may have been a translation of his true Celtic name. As an English name, Samson was common during the Middle Ages, having been introduced by the Normans. It is currently most common in Africa, especially in countries that have an British colonial past.
As a Christian name, Ruth has been in use since the Protestant Reformation. In England it was associated with the archaic word ruth meaning "pity, compassion" (now only commonly seen in the word ruthless). The name became very popular in America following the birth of "Baby" Ruth Cleveland (1891-1904), the daughter of President Grover Cleveland.
This name spiked in popularity in several places around the world in 1954 after Pope Pius declared it to be a Marian year, in honour of the Virgin Mary. A similar declaration in 1987 did not have as marked an effect.
Apart from royalty, this name was only moderately popular in France during the Middle Ages. After the French Revolution, when Louis XVI was guillotined, it became less common.
The Normans brought the name to England, where it was usually spelled Lewis, though the spelling Louis has been more common in America. Famous bearers include French scientist Louis Pasteur (1822-1895), French actor Louis de Funès (1914-1983), Scottish author Robert Louis Stevenson (1850-1894), who wrote Treasure Island and Dr Jekyll and Mr Hyde, and American jazz musician Louis Armstrong (1901-1971).
As an English name it did not become common until after the Protestant Reformation, despite a handful of early examples during the Middle Ages. It was however used earlier on the European continent, being borne by several European royals, such as the 9th-century Judith of Bavaria.
This name (in various spellings) has been common among European royalty, being borne by ruling queens of Naples, Navarre and Castile. Another famous bearer was Joan of Arc, a patron saint of France (where she is known as Jeanne d'Arc). She was a 15th-century peasant girl who, after claiming she heard messages from God, was given leadership of the French army. She defeated the English in the battle of Orléans but was eventually captured and burned at the stake.
Other notable bearers include the actress Joan Crawford (1904-1977) and the comedian Joan Rivers (1933-2014), both Americans.
Though the etymology is unrelated, this is the name of a mountain on the island of Crete where, according to Greek myth, the god Zeus was born.
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 Britain the parallel form Alice, derived via Old French, has historically been more common than Adelaide, though this form did gain some currency in the 19th century due to the popularity of the German-born wife of King William IV, for whom the city of Adelaide in Australia was named in 1836.