Ok - for instance JJ Jenkins: he is classified as "Free Person of Color" because he fell into this category:
In some cases, planters or other relatively wealthy white men took slave women or free women of mixed race as concubines. If the woman was enslaved, the man might free her and their children, adding to the class of free people of color. Such planters often sent their mixed-race sons to France for education and service in the military, and sometimes settled property on them.
W.E. Dubois is Creole due to him having French Creole Ancestry:
was born three years after the American Civil War on February 23, 1868, in Great Barrington, Massachussetts.
His mother was Mary Sylvania Burghardt, a short and attractive brown-skinned woman who worked most of her life as a domestic in Great Barrington.His mulatto father, Alfred Du Bois, was a descendant of French Huguenot ancestry from Haiti and a barber by trade.
Du Bois knew much less about his father, although he was able trace his father's ancestry to a seventeenth-century white French Huguenot farmer residing in the west Indies named Chretien Du Bois. Further down the lineage was Du bois's grandfather, the short, stern Alexander Du Bois, who was light enough to pass for white but chose a black identity instead.Du Bois was prolific as a scholar, author, editor, writer, and social activist. He combined his scholarship with organized social protest from 1896 to 1963, producing an enormous amount of written work in history and sociology as well as critical pieces about current events. His amazing ability to utilize the unique insights of so many disciplines gave his work depth and beauty.
French Creole | Homer Plessy