Steffi Graf was born on 14th June, 1969 in Germany.
I think it was Steffi Graff.
Before 1968, during the era of the amateur player, it was Suzanne Lenglen, with 15 titles. After 1967, when tennis was made "open", Martina Navratilova, with 11 titles. And with a career that bridged both eras, Margaret Court won 13 French titles.