Ratified in 1868, Congress and the courts have applied the 14th Amendment's Equal Protection Clause to many aspects of public life over the past 150 years. The Fourteenth Amendment addresses many aspects of citizenship and the rights of citizens.More in The Constitution. The 13th Amendment formally abolished slavery. The 14th Amendment established African Americans as equal citizens of the United States. The Citizenship Clause broadly defines citizenship, superseding the Supreme Court's decision in Dred Scott v. HISTORY 13-18, 47-48 (1993). 1870 (University of North Carolina Press 1978). 2. Black voter registration, particularly in the South, was very low, and in Mississippi only 6.7 percent of eligible blacks were registered to vote in 1964. The primary source documents on this page highlight pivotal moments in the course of American history or government.