Final answer:
European explorers believed they could claim already populated lands due to the concept of 'terra nullius', 'manifest destiny', and their belief in the superiority of their own culture.
Step-by-step explanation:
European explorers believed they could simply claim lands for their home countries, even though these lands were already populated because of the concept of 'terra nullius'. Terra nullius refers to the belief that land belonging to indigenous peoples was considered empty or unoccupied, and therefore eligible for European control and settlement. Additionally, the explorers believed in the idea of 'manifest destiny', which convinced them that it was their God-given right to expand and colonize new territories. Moreover, the explorers had superior military technology and believed in the superiority of their own culture, which justified their actions of colonization and claiming of territories.
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