... the careful distortion of the history of a nation, perpetrated by its enemies, in order to better fight it. And a distortion as monstrous as possible, with the goal of achieving a specific aim: the moral disqualification of the nation, whose supremacy must be fought in every way possible.

— as cited in Alfredo Alvar's book, La Leyenda Negra (1997:5)

The black legend of empires would be the result of the following combined factors:

• The combined propaganda attacks and efforts of most smaller powers of the time, as well as defeated rivals.
• The propaganda created by the many rival power factions within the empire itself against each other as part of their struggle to win more power.
• The self-criticism of the intellectual elite, which tends to be larger in larger empires.
• The need of the new powers consolidated during the empire's life or after its dissolution to justify their new prevalence and the new order.

The defining feature of a black legend is that it has been fabricated and propagated intentionally. Black legends also tend to share certain additional elements:

• Permanent decadence
• Degenerated or polluted version of something else.
• Accidentality of merit.
• Obligatory moral actions.
• Natural moral inferiority and irredeemable character.

Narrations of black legends tend to include: Strong pathos, combined with a narrative that is easy to follow and emotionally loaded, created by:

• Detailed, gruesome and morbid descriptions of torture and violence
• Sexual elements
• Ignorance