African-American heritage of presidents of the United States
Calvin Coolidge's mother Victoria Moor was claimed to be of a mixed-race family in Vermont. Vaughn noted that her surname was derived from "Moor", a European term for people of North Africa. He did not note that another meaning of her surname is the landscape feature of moor or bog. People's surnames were often based on such landscape features when surnames became generally adopted in 14th century England. Moor/Moore is a common name in England, Scotland, and Ireland.
Black people
The term "Moors" has been used in Europe in a broader, somewhat derogatory sense to refer to Muslims, especially those of Arab or Berber descent, whether living in North Africa or Iberia. Moors were not a distinct or self-defined people. Medieval and early modern Europeans applied the name to Muslim Arabs, Berbers, Black Africans and Europeans alike.