As an English name, it became popular due to the Fleetwood Mac song Rhiannon (1976), especially in the United Kingdom and Australia.
Geoffrey based parts of Merlin's character on Myrddin Wyllt, a legendary madman and prophet who lived in the Caledonian Forest. Other parts of his life were based on that of the historical 5th-century Romano-British military leader Ambrosius Aurelianus (also known as Emrys Wledig). In Geoffrey's version of the tales and later embellishments Merlin is a magician and counselor for King Arthur.
In the English-speaking world this name has been occasionally given since the early 20th century. It started rising in America after the variant Lorelai was used for the main character (and her daughter, nicknamed Rory) on the television series Gilmore Girls (2000-2007).
The Cornish form of this name, Jennifer, has become popular in the English-speaking world.
As an English name it has been in use since the Middle Ages, originally in the form Clare, though the Latinate spelling Clara overtook it in the 19th century and became very popular. It declined through most of the 20th century (being eclipsed by the French form Claire in English-speaking countries), though it has since recovered somewhat.
As an English name, Chloe has been in use since the Protestant Reformation. It started getting more popular in the 1980s in the United Kingdom and then the United States. It was the most popular name for girls in England and Wales from 1997 to 2002. This is one of the few English-language names that is often written with a diaeresis, as Chloë.
As an English name, Caleb came into use after the Protestant Reformation. It was common among the Puritans, who introduced it to America in the 17th century.
Arthur is the name of the central character in Arthurian legend, a 6th-century king of the Britons who resisted Saxon invaders. He may or may not have been based on a real person. He first appears in Welsh poems and chronicles (perhaps briefly in the 7th-century poem Y Gododdin and more definitively and extensively in the 9th-century History of the Britons [1]). However, his character was not developed until the chronicles of the 12th-century Geoffrey of Monmouth [2]. His tales were later taken up and expanded by French and English writers.
The name came into general use in England in the Middle Ages due to the prevalence of Arthurian romances, and it enjoyed a surge of popularity in the 19th century. Famous bearers include German philosopher Arthur Schopenhauer (1788-1860), mystery author and Sherlock Holmes creator Arthur Conan Doyle (1859-1930), and science-fiction author Arthur C. Clarke (1917-2008).
The name has been used by kings of Scotland, Poland and Yugoslavia, emperors of Russia, and eight popes. Other notable bearers include English poet Alexander Pope (1688-1744), American statesman Alexander Hamilton (1755-1804), Scottish-Canadian explorer Alexander MacKenzie (1764-1820), Russian poet Alexander Pushkin (1799-1837), and Alexander Graham Bell (1847-1922), the Scottish-Canadian-American inventor of the telephone.