mestizo vs mulatto

mestizo

noun
  • A person of mixed ancestry, especially one of Spanish and Native American heritage. 

  • a person of mixed ancestry, especially one of native Filipino and Spanish or Chinese ancestry, such as that of the Spanish mestizos and Chinese mestizos from the Spanish Colonial Era of the Philippines. 

mulatto

noun
  • A person of mixed black and white descent, especially a person with one black and one white parent or two mulatto parents. 

How often have the words mestizo and mulatto occurred in a corpus of books? (source: Google Ngram Viewer )