The name was originally used among early Christians in honour of the saint, as opposed to the classical character. In England it was commonly spelled Ellen during the Middle Ages, and the spelling Helen was not regularly used until after the Renaissance. A famous bearer was Helen Keller (1880-1968), an American author and lecturer who was both blind and deaf.
In the English-speaking world the form Christine was more popular for most of the 20th century, though Christina eventually overtook it. Famous bearers include actress Christina Ricci (1980-) and singer Christina Aguilera (1980-).
In England, this Latin form has been used alongside the vernacular forms Ann and Anne since the late Middle Ages. Anna is currently the most common of these spellings in all English-speaking countries (since the 1970s), however the biblical form Hannah is presently more popular than all three.
The name was borne by several Russian royals, including an 18th-century empress of Russia. It is also the name of the main character in Leo Tolstoy's novel Anna Karenina (1877), about a married aristocrat who begins an ultimately tragic relationship with Count Vronsky.
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.