This trait was first noted as far back as the 17th century, but became extensively documented in the last part of the 18th and the 19th century. It was Sarah Baartman's 19th century case that brought the elongated labia back out for discussion. For many years, the identification of Baartman was questioned because she demonstrated this feature. In the Gender and Science Reader, elongated labia minora were said to be portrayed by a "Negro." So it is because of this trait that Baartman was considered to be part of the so-called "inferior race".
Labia may also be shaped by intentional labia stretching, usually done by an older aunt on girls beginning at the age of five, a practice that formerly fell into the category of Type IV female genital mutilation. In 2008, The World Health Organisation reclassified the practice as a body modification due to a perceived lack of harm and a reported much more positive perception of women's sexuality by those who practice it.
closeup of enlarged labia, spread
Khoikhoi women with pendulous labia visible