An elderly veteran tells his life story, tracing noble family origins and youthful education, recounting ancestors' deeds and a mother's lineage, then describing martial training and campaigns—including service in Italy and participation in conquest efforts—followed by long voyages through the two Indies. He narrates duels, battles, dangerous escapes, and the precarious rewards of military service, attributing many survivals to devotion to Our Lady of Atocha. The memoir interweaves genealogical anecdotes, travel episodes, and reflections on honor, faith, aging, and the diminished fortunes of a retired soldier.