According to Wikipedia's entry on this movie, Hammer had acquired the rights to make the movie in 1958, but the British censors wouldn't allow its production (no reason for this is cited in the entry), so the rights were then sold to AIP. I wonder what a British production would have done, compared to this Italian-American one. You can read the pressbook here.
a different sort of vampire flick, i liked this one..
A larger budget would have helped. I still like it. It has lots of atmosphere. And it has Vincent Price.