From 1869 to 1875, activists associated with the National Woman Suffrage Association, including Susan B. Anthony and Elizabeth Cady Stanton, argued that the United States Constitution guaranteed women’s right to vote. Adam Winkler argues that this movement–which the suffragists termed the “New Departure”–rested on an innovative theory of constitutional interpretation that would become the dominant mode of constitutional construction in the twentieth century. Now recognizable as “living constitutionalism,” the suffragists’ approach to constitutional interpretation was harshly critical of originalism–the dominant mode of nineteenth-century interpretation–and proposed to construe textual language to keep up with changing societal needs. This Article analyzes the intellectual currents that made plausible the suffragists’ embrace of an evolutionary interpretive methodology, traces the development of the suffragists’ approach as they fought for the franchise in Congress and in the courts, and reveals how radical suffragists encountered the obstacles of originalism at every turn. Correcting the error of constitutional historians who assert that living constitutionalism first emerged in the Progressive Era, this Article stakes a claim for recognizing woman suffragists as important innovators at the forefront of modern constitutional thought.