The primary, if not singular, purpose of the Fourteenth Amendment’s Citizenship Clause was to override the moral atrocity of the Supreme Court’s 1857 decision in Dred Scott v. Sandford. There, the nation’s highest court held that the US-born descendants of African slaves were not (and could never become) citizens, effectively relegating an entire race of people to permanent alienage in the country where they and their ancestors had lived and died for multiple generations. While the 39th Congress clearly sought to remove race-based barriers to citizenship, it did not do so by returning to a common law rule derived from feudalism and perpetual allegiance owed to a sovereign by virtue of some accident of birth upon his land. Rather, informed by republican principles, Congress sought to enshrine birthright citizenship for all persons who, like the US-born descendants of African slaves, were subject to the fullest extent of the United States’ political jurisdiction. At the same time, Congress debated and revised the language of both Fourteenth Amendment and the Civil Rights Act of 1866 that preceded it in a purposeful attempt to clarify that much larger categories of individuals were excluded from birthright citizenship under the Constitution than were excluded under the old common law rule.
Perhaps nowhere is this more evident than in the debates surrounding Congress’ first effort to establish the citizenship of the newly freed slaves—the Civil Rights Act of 1866. This piece of legislation for the first time in American history defined the parameters of birthright citizenship, making citizens of “all persons born in the United States and not subject to any foreign power, excluding Indians not taxed.” Senator Lyman Trumbull—an accomplished attorney from Illinois and one the principal authors of the Act’s citizenship clause—recounted for his fellow members of Congress how that language arose from intentional efforts to exclude from citizenship those who owed only a qualified and temporary allegiance under the common law rule. He explained that they initially considered the language “all persons born in the United States and who owe allegiance to it,” but rejected it precisely because “upon further investigation it was found that a sort of allegiance was due to the country from persons temporarily resident in it whom we would have no right to make citizens, and that form would not answer.”