to the United States Constitution (1971, minimum voting age must be 18 or younger) Voting rights in the United States References Informational notes Citations Bibliography External links Fifteenth Amendment and related resources at the Library of Congress CRS Annotated Constitution: Fifteenth Amendment "Campaign to Commemorate 150th Anniversary of the 15th Amendment" Zinn Education Project, 2020. Fifteenth Amendment to the United States Constitution 1870 in American politics Aftermath of the American Civil War Amendments to the United States Constitution History of voting rights in the United States Presidency of Ulysses S. Grant Reconstruction Era