The competing ideologies of nation and monarchy had a troubled beginning in the 19th century, insomuch as they derived partly from two opposing sources of legitimacy. However, from the 1830s on, their supporters achieved the establishment of an interspecific and mutually advantageous relationship. The nation gradually managed to prevail over the monarchy, justifying its presence in national terms. However, the monarchy possessed something longed for by liberal nationalists: historical legitimacy. Thus, the crown served Romantic nationalism in its search for national foundations and to generate national emotions of a collective sense of belonging. This article analyses this process by focusing on the Spanish case and using a vast range of cultural sources. I reason that the monarchy’s history was intensively used in Isabel II’s reign (1833–1868), both by the monarch herself as well as nationalist elites, to legitimate and justify their presence in the liberal world. The article is divided into three sections. The first part locates the problem into a general process that touched all the crowned heads of Europe. The second section studies the appeal of exemplary medieval monarchs in the liberal hunt for national roots. The final one focuses on the particular case of Isabel the Catholic because of the remarkable prominence it acquired.