The discovery of Horatio Greenough, the “pioneer of functionalism,” and the reevaluation of his architectural ideas in the mid-1930’s would subsequently affect the architectural debates in the U.S. in the field of historiography. The history of history, as it is called, of national identification in architecture is traced here, through extensive research on the references to him in narratives by the classicist camp towards the first establishment of coherent images of the classic tradition of American architecture both in theory and in practice in 1947, with the investigation into the prehistory when the two they considered contradicted each other.