In this ambitious volume, Professor David R. Upham offers a comprehensive account of the original understanding of the Fourteenth Amendment, shedding new light on its often-overlooked Privileges or Immunities Clause. Drawing on a close textual reading as well as a wide range of primary sources—some newly discovered—Upham argues that the framers intended the amendment as a measure designed to strengthen existing constitutional protections for the rights of both human personhood and American citizenship. Upham contends that the amendment secures for all individuals the basic rights to life, liberty, and property through guarantees of due process and equal protection, while also reaffirming the birthright principle that grants citizenship to nearly all born on U.S. soil. Moreover, the Fourteenth Amendment safeguards longstanding privileges and immunities of citizenship, including the rights to travel, engage in commerce, speak freely, bear arms, and enjoy protection from racial discrimination and other forms of civic exclusion. By recovering the Amendment’s original meaning, this book reshapes our understanding of constitutional rights and citizenship, with far-reaching implications for contemporary legal and political debates.