Short answers, pulled from the story.
The Reconstruction Amendments are the Thirteenth, Fourteenth, and Fifteenth Amendments, adopted between 1865 and 1870 in the five years following the Civil War. The Thirteenth abolished slavery, the Fourteenth established citizenship rights and equal protection, and the Fifteenth prohibited denying the vote based on race, color, or previous condition of servitude.
The Thirteenth Amendment was ratified on the 6th of December 1865 and proclaimed part of the Constitution on the 18th of December 1865. It abolished slavery and involuntary servitude, except as punishment for a duly convicted crime, and was the first constitutional amendment in more than sixty years.
The Equal Protection Clause required every state to provide equal protection under the law to all persons within its jurisdiction. It served as the legal basis for Brown v. Board of Education in 1954, which struck down racial segregation in public schools, and for Loving v. Virginia in 1967, which struck down laws against interracial marriage.
Around 1900, former Confederate states passed laws including poll taxes, literacy tests administered by white staff, residency rules, and grandfather clauses that created exemptions for white voters. These measures drove nearly all Black voters, and tens of thousands of poor white voters, off registration rolls entirely. Most Black Southerners did not regain practical voting rights until the mid-1960s federal civil rights legislation.
The Slaughter-House Cases in 1873 limited rights under the Fourteenth Amendment's Privileges or Immunities Clause, and Plessy v. Ferguson in 1896 originated the phrase "separate but equal," giving federal approval to Jim Crow laws. These rulings eroded the protections the amendments had been designed to guarantee.
The full benefits were not realized until the Supreme Court's decision in Brown v. Board of Education in 1954, the Civil Rights Act of 1964, and the Voting Rights Act of 1965. The Twenty-fourth Amendment in 1964 also abolished poll taxes in federal elections, and Harper v. Virginia State Board of Elections in 1966 extended that ban to state elections.