Which amendment guaranteed all adult males the right to vote during the Reconstruction era?

The Fifteenth Amendment, ratified in 1870, was specifically designed to ensure that the right to vote could not be denied to any citizen of the United States based on "race, color, or previous condition of servitude." This was a significant milestone during the Reconstruction era, as it aimed to protect the voting rights of newly freed African American men following the Civil War.

In the context of the time, prior amendments had addressed other aspects of civil rights and liberties. The Thirteenth Amendment abolished slavery, while the Fourteenth Amendment focused on citizenship and equal protection under the law, but neither directly concerns voting rights for adult males. The Nineteenth Amendment, on the other hand, pertains to women's suffrage and was ratified much later, in 1920. Therefore, the Fifteenth Amendment stands out as the key legislative achievement aimed at safeguarding the voting rights of adult males during Reconstruction.