Who is Madam C.J. Walker in the nonfiction book, When and Where I Enter: The Impact of Black Women on Race and Sex in America?

Named Sarah Breedlove at birth, Walker is an orphan who marries at age fourteen and is soon widowed. She works in domestic situations until she discovers a recipe for thickening hair. She establishes a lab, creates a number of products and employs thousands in her business enterprise.