Alonso Gonzalez de Nejera's Desengano y reparo de la guerra del Reino de Chile (1614), is an essential text for understanding the conquest of Chile in the early 17th century. This paper summarizes the most noteworthy challenges that the editor faced in the ecdotic field (from tracing the manuscript and the printed editions to the transcription and binding of the final text) and the hermeneutic field. It takes into account the extensive passages the author dedicated to describe Chile's geography, flora and fauna, the Mapuche people and the reasons behind the Spanish military's challenges in Araucania.