Allen C. Guelzo's Reconstruction: A Concise History is a gracefully-written interpretation of Reconstruction as a spirited struggle to re-integrate the defeated Southern Confederacy into the American Union after the Civil War, to bring African Americans into the political mainstream of American life, and to recreate the Southern economy after a Northern, free-labor model.
A well-balanced assessment of the achievements and lost opportunities of an era, Allen Guelzo's Reconstruction: A Concise History is a solid introduction to the topic. It's also a fitting gateway for those curious enough to want to investigate the more in-depth treatments of all kinds that populate the modern Reconstruction bookshelf.