I was invited to contribute to this special edition of the e-Journal of Portuguese History with a short piece on the late Professor Oliveira Marques and his contribution to Portuguese historiography, more specifically his contribution to our understanding of the First Republic (1910-1926). As someone who began his graduate studies in 1992 having completed an undergraduate degree outside Portugal, and having set out to write a thesis about Portugal’s intervention in World War One, I owe—like all other scholars of the period—an immense debt of gratitude to Oliveira Marques, who over the course of some forty years of febrile activity contributed enormously to our understanding of the period. But this is a debt of gratitude qualified by the realization that there were certain limitations to Oliveira Marques’ writings on the subject of the First Republic, and that these ought to be borne in mind.