The Legal Theory Bookworm recommends The Reconstruction Amendments: The Essential Documents (Volume 1) (and Volume 2), edited by Kurt Lash. Here is a description:
Ratified in the years immediately following the American Civil War, the Thirteenth, Fourteenth, and Fifteenth Amendments to the United States Constitution—together known as the Reconstruction Amendments—abolished slavery, safeguarded a set of basic national liberties, and expanded the right to vote, respectively. This two-volume work presents the key speeches, debates, and public dialogues that surrounded the adoption of the three amendments, allowing us to more fully experience how they reshaped the nature of American life and freedom.
Volume I outlines a broad historical context for the Reconstruction Amendments along with materials related to the Thirteenth Amendment, which abolished slavery, while Volume II covers the Fourteenth and Fifteenth Amendments on the rights of citizenship and enfranchisement. The documents in this collection encompass a sweeping range of primary sources, from congressional talks to court cases, public speeches to newspaper articles. As a whole, the volumes meticulously depict a significant period of legal change even as they illuminate the ways in which people across the land grappled with the process of constitutional reconstruction. Filling a major gap in the literature on the era, The Reconstruction Amendments will be indispensable for readers in politics, history, and law, as well as anyone seeking a better understanding of the post–Civil War basis of American constitutional democracy.
And from the reviews:
I just finished teaching a course on the Reconstruction Amendments and Acts at Stanford Law School, using a judicious sub-set of Kurt Lash's marvelous set of original source materials. This opens up possibilities for teaching as well as research which never existed before. The students commented especially on how helpful Lash's introductory essays to each part of the materials were. This publication is a magnificent academic achievement and a public service.--Michael W. McConnell, Director Stanford Constitutional Law Center

