This essay considers the growth of historiographical writing in fifteenth-century Iberia within the context of mass conversions of Jews to Christianity. It takes the writing of the convert Pablo de Santa María (ca. 1351-1435) as a test case for considering the emergence of historiographical writing directly informed by the events of 1391, in which many thousands of Jews were forcibly converted to Christianity. By reading Pablo’s poem Siete edades del mundo (Seven Ages of the World) in light of his biblical exegesis and anti-Jewish polemic, it is possible to show how issues relevant to Pablo’s conversion, including his exegetical polemic with Judaism, directly affect his historiographical writing and shape his use of standard tropes of fifteenth-century Castilian historiography. This suggests that, while there may be no uniquely “converso voice” in history writing, some fifteenth-century historiography is clearly informed by issues of particular relevance to conversos. At the same time, it implies that some fifteenth-century Christian historiography, like that of Sephardic Jews after the expulsion of 1492, grew from earlier historiographical and polemical traditions that transcend any single catalyzing event such as the trauma of 1391.