He presents his narrative as an alternative to the critical writings of Bartolomé de Las Casas, whose descriptions of Spanish treatment of native peoples emphasized the cruelty of the conquest.

He also criticized the histories of the hagiographic biographers of Hernán Cortés, specifically that of Francisco López de Gómara, who Díaz del Castillo believed minimized the role of the 700 enlisted soldiers instrumental to conquering the Aztec Empire.

In his eyewitness account, narrated in the first-person plural "we," Díaz del Castillo strongly defends the actions of the conquistadors while emphasizing their humanity and honesty.

"[citation needed] The history is occasionally uncharitable about Cortés, whom Díaz del Castillo felt had taken most of the glory for himself while intentionally ignoring the efforts of the other Spaniards and their indigenous allies.

[4] Though Díaz del Castillo justifies his and the other Spaniards’ actions through the lens of a just war, he does express some regret over the destruction of Tenochtitlán, writing, "When I beheld the scenes around me, I thought within myself, this was the garden of the world.