The name Natalie is actually derived from the Latin word for 'day of birth' or 'natal day' which is Dies Natalis. With the rise of the Holy Roman Empire, the phrase most commonly referred to the birth day of Jesus Christ. As a name, its origins lie in the custom of naming one's child Natalia (or its equivalents) if they were born on Christmas day, in honour of the celebration. This custom translated into most Romance languages (Italian, French, Spanish, Romanian etc...) and both France and Italy claim to have popularized the name during the Renaissance period.
Baby name trends in the US have seen Natalie rise in popularity in recent years, whilst its use in European countries has headed in the opposite direction. The name, however, retains the number one spot for girls born on Christmas day, and comes second only to Holly in the naming of girls born during the festive season.