The Civil War and the XIII Amendment ended slavery. Within a few years the XIV and XV
amendments granted full citizenship to the former slaves and others.
(Women and Indians would have to wait until later).
Amendment XIII to the US Constitution 1865
Section 1. Neither slavery nor involuntary servitude,
except as a punishment for crime whereof the party shall have been duly
convicted, shall exist within the United States, or any place subject
to their jurisdiction.
Amendment XIV to the US Constitution 1868
Section 1. All persons born or naturalized in the United
States, and subject to the jurisdiction thereof, are citizens of the
United States and of the state wherein they reside. No state shall make
or enforce any law which shall abridge the privileges or immunities of
citizens of the United States; nor shall any state deprive any person
of life, liberty, or property, without due process of law; nor deny to
any person within its jurisdiction the equal protection of the laws.
Amendment XV to the US Constitution 1870
Section 1. The right of citizens of the United States to
vote shall not be denied or abridged by the United States or by any
state on account of race, color, or previous condition of servitude.
However the Southern States were not satisfied so they enacted laws continuing racial segregation. These laws
are generally called Jim Crow laws. What was segregated? Pretty much every aspect of life. Schools,
restaurants, hotels, public transportation, swimming pools,
movies, restrooms, water fountains. States enacted laws to discourage blacks from
voting by requiring literacy tests or imposing poll taxes. There were
even laws against interracial marriage called miscegenation laws.
The
federal government, satisfied at first to reestablish the Union did not press
the issue. Legal challenges such as Plessy v. Ferguson in 1896 established the
legitimacy of the Jim Crow laws. Plessy v. Ferguson established the
doctrine of "separate but equal."
Jim Crow laws continued in force albeit under considerable pressure. In
1954 when the Supreme Court decided Brown v. Board of Education they overturned Plessy and Jim Crow really began to unravel. The
Civil Rights Act of 1964 and the Voting Rights Act of 1965 ended the
Jim Crow laws just 100 years after the Civil War ended at Appomattox
Courthouse.
So that was the end of racial segregation as a legal device or so it would seem.
It also ended the dominance of Democrats in Louisiana and especially
New Orleans. Conservative whites in the New Orleans area turned to the
Republicans and haven't turned back. When blacks gained numerical
superiority in the city in 1978 the city reverted to Democrat. Today the dichotomy is fierce Democrat=Black and Republican=White.