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 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-).