Marvel, which means marvel literally and "wonderful," doesn't seem like it would have been a popular baby name, yet it ranked from 1889 until 1941 for girls, highest at #487 in 1899. First appearing long before Marvel Comics, this female name is considered a variant of the Latin name Maravilla. Other spellings include Marivel and Marvella. It also ranked for boys between 1896 and 1910, the highest ranking being #769 in 1899 and a short reappearance in 1929. These rankings, however, come from a time when fewer babies were being born, so altogether it wasn't an extremely common name. Today it is given to as few as 8 girls and 13 boys, and for the most part it has been unused for girls after the late 1970's.
Marvel has a few namesakes. First is Marvel Crosson, the pioneer "aviatrix" of 1929 who set a new altitude record for female pilots. Second, the character Marvel from the Hunger Games series. Third, Marvel Turlock from the book White Oleander. There may be others but it is increasingly hard to find any namesakes when every kind of search results in Marvel Comics. But, let that be a strong reminder that if you bestow this name upon your child, every person's first thought will be "like the comics." I suggest using it as a middle name - especially for the comic book fan.