In the Middle Ages this name was common in England due to the popularity of medieval tales about the Trojan War. It subsequently became rare, but was revived in the 20th century.
In the United States this form was much less common than Isabel until the early 1990s, when it began rapidly rising in popularity. It reached a peak in 2009 and 2010, when it was the most popular name for girls in America, an astounding rise over only 20 years.
A famous bearer is the Italian actress Isabella Rossellini (1952-).