15th Amendment Ratification Explained: Timeline and Enforcement

Ratification of the 15th Amendment was completed on February 3, 1870, when Iowa became the 28th state to approve it and cleared the three-fourths threshold Article V requires.¹ Secretary of State Hamilton Fish issued the official certification on March 30, 1870, making the amendment’s prohibition on race-based voting restrictions part of the Constitution and enforceable nationwide.² It was the last of the three Reconstruction Amendments.

What the Amendment Actually Says

The text is short. Section 1 declares that the right 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.”³ Section 2 gives Congress the power to enforce the amendment through legislation.⁴

One distinction shapes everything that came after. The amendment does not grant a right to vote. It only bars governments from using race as the reason to deny one. Every other voting qualification, from literacy to property to age, stayed within state authority.

The Article V Threshold

Article V requires two steps. Two-thirds of both chambers of Congress must approve an amendment, then three-fourths of state legislatures must ratify it.⁵ When Congress sent the 15th Amendment to the states in February 1869, the Union had 37 states, which meant 28 legislatures had to say yes.¹ That total mixed northern states with former Confederate states still working through Reconstruction, and support for Black suffrage was uncertain in both regions.

How Reconstruction Shaped the State Votes

The Military Reconstruction Act of 1867 had divided the former Confederacy, except Tennessee, into five military districts under Army command. To end that occupation and regain seats in Congress, those states had to write new constitutions and ratify the 14th Amendment.⁶

By 1869 most had cleared those hurdles, but Virginia, Mississippi, Texas, and Georgia had not been fully restored. Congress added a new condition in separate readmission acts passed in 1869 and 1870: those four states also had to ratify the 15th Amendment. This condition was not in the original 1867 Reconstruction Act, which predated the amendment by two years. The leverage was blunt. A state that refused to ratify stayed under military oversight with no voice in national governance, which converted readmission into a mechanism for delivering votes the amendment might not otherwise have received.

The Ratification Timeline

Nevada ratified first, on March 1, 1869, just three days after Congress proposed the amendment. Over the next year, states across the country debated and voted.

The process was not close to unanimous. California, Delaware, Kentucky, Maryland, New Jersey, Oregon, and Tennessee rejected the amendment outright. Several did not formally ratify until the mid-20th century.

Iowa’s vote on February 3, 1870 was the 28th and decisive one.¹ By the time Hamilton Fish issued his proclamation on March 30, a 29th state had also approved. Fish’s certification declared the amendment “valid to all intents and purposes as part of the Constitution of the United States.”² Once the certificates were processed, no state could legally reverse its approval.

What the Text Left Out

The final amendment banned racial discrimination in voting and nothing else. It said nothing about poll taxes, literacy tests, or property requirements. That silence was not an oversight. Broader drafts had circulated in Congress during 1869, some of them abolishing literacy and property tests, some protecting the right to hold office, some addressing national origin or religion. Each of those provisions cost votes somewhere. The final text was as narrow as it was because a narrower amendment was the only version that could reach two-thirds in both chambers and 28 state legislatures.

How States Worked Around the Amendment

Within roughly a decade, southern states built a system of voter suppression that stayed within the amendment’s literal text while destroying its purpose:

Poll taxes: flat fees required before voting, set high enough to price out most Black voters and many poor white voters.
Literacy tests: exams administered by local registrars with broad discretion over difficulty, with white applicants routinely getting easier versions or being waved through.
Grandfather clauses: laws exempting anyone whose ancestors could vote before 1866 or 1867 from literacy and property requirements, which by design excluded Black citizens who could not have voted before 1870.
White primaries: the Democratic Party declared itself a private organization and barred Black voters from its primaries, which in the one-party South decided general elections.

The Supreme Court reinforced these workarounds. In United States v. Reese (1876), the Court held that the 15th Amendment authorized Congress to punish only voting denials explicitly based on race.⁷ A facially neutral literacy test was almost impossible to challenge under that standard.

The Enforcement Acts

Congress moved quickly after ratification. The Enforcement Act of May 1870 prohibited groups from banding together or disguising themselves to violate citizens’ constitutional rights, and authorized the president to use military force to protect voters from intimidation.⁸ A second Enforcement Act followed in 1871, aimed at the Ku Klux Klan. Both statutes were the first uses of Section 2. After Reese narrowed the constitutional ground, and as northern political will for Reconstruction faded, federal troops withdrew and the Acts went largely unused for close to a century.

The Voting Rights Act of 1965

Real enforcement did not arrive until 1965. The Voting Rights Act, passed under Section 2 of the 15th Amendment, banned literacy tests and other discriminatory practices. Section 5 required certain jurisdictions with histories of voter discrimination to get federal approval, called preclearance, before changing any voting law. Covered jurisdictions had to prove to the U.S. Attorney General or a federal court in Washington, D.C. that a proposed change would not discriminate against minority voters. Black voter registration and representation across the South rose sharply under the Act, and Congress renewed it several times.

Shelby County v. Holder

In 2013, the Supreme Court struck down Section 4 of the Voting Rights Act in Shelby County v. Holder. Section 4 contained the formula that identified which jurisdictions were subject to preclearance. The Court held that the formula, based on data from the 1960s and 1970s, could no longer justify treating some states differently from others. Section 5 remains on the books, but without a coverage formula there is no way to apply it.⁹ Congress has not passed a replacement. Election-law oversight has largely returned to the states.

The Split in the Women’s Suffrage Movement

The 15th Amendment fractured the women’s rights movement for two decades. In 1869, Elizabeth Cady Stanton and Susan B. Anthony founded the National Woman Suffrage Association, which opposed the amendment as written because it extended voting rights only to men. The rival American Woman Suffrage Association supported the amendment and pursued women’s suffrage separately. The two organizations did not reunite until 1890, and women’s suffrage was not secured until the 19th Amendment was ratified in 1920, fifty years after the 15th.

1
Congress.gov. Civil War Amendments (Thirteenth, Fourteenth, and Fifteenth Amendments)
2
Iowa Department of Cultural Affairs. Secretary of State Hamilton Fish’s Certification of the 15th Amendment’s Ratification
3
National Archives. 15th Amendment to the U.S. Constitution: Voting Rights (1870)
4
Legal Information Institute. 15th Amendment
5
Congress.gov. Overview of Article V, Amending the Constitution
6
United States Senate. The Civil War: The Senate’s Story
7
Justia U.S. Supreme Court Center. United States v. Reese
8
United States Senate. The Enforcement Acts of 1870 and 1871
9
Justia U.S. Supreme Court Center. Shelby County v. Holder