[4] Her 2016 book, "Imperiofobia y leyenda negra: Roma, Rusia, Estados Unidos y el Imperio español" (Empire-phobia and Black Legend: Rome, Russia, United States and the Spanish Empire) became a bestseller and won numerous awards.
The book is a work of advocacy, with a preface that declares that the author doesn't plan on being exhaustive but on putting forward the lesser known information about various empires and their ideological rivals.
In Fracasología she argues that from the rise of the Bourbon dynasty, Spanish intellectuals have "fossilised self-contempt and uncritical admiration for modernity among Spaniards".
"[10] Ricardo García Cárcel [es], Chair of Early Modern History at the Autonomous University of Barcelona and author of La leyenda negra: historia y opinión (1992), argues that, whether Roca Barea likes it or not, it is not currently possible to find any European or American historian with scientific credentials who accepts the extremes of the so-called Leyenda negra ("Black Legend").
He also highlights Roca Barea's dismissal of Spanish atrocities in the Americas, citing exceptionally well-documented practices such as amputation, burning and mass killings.
[8] When it comes to literary style, Mainer describes the prose in Fracasología as "capricious and impulsive", sprinkled with an "abundant" yet "arbitrary" bibliography with a number of mistakes.
[8] She received significant praise from Peruvian Nobel Prize Winner, Mario Vargas Llosa, who considered Imperiofobia a "book of rigorous scholarship" which is "combative, deep, controversial and reads without pause".