Final answer:
The primary driving force for the creation of the Black Legend centered around Spain was Spain's wide use of torture and cruelty in its treatment of Native Americans.
Step-by-step explanation:
The primary driving force for the creation of the myth of competition among European nations, as part of the Black Legend centered around Spain, was Spain's wide use of torture and cruelty in its treatment of Native Americans. English writers seized on the idea of Spanish ruthlessness to support their own colonization projects. By demonizing the Spanish, they justified their own efforts as more humane, despite the fact that all European colonizers shared a disregard for Native peoples.