The stated justifications for this included the spread of Christianity, the duty to bring civilization to barbarian peoples, the natural right to explore and trade freely with other peoples, and the right to settle and cultivate uninhabited or uncultivated land.
These explanations provided for this included the propagation of Christianity, the responsibility to bring modernity to primitive populations, the natural liberty to explore and exchange goods with other countries, and the right to establish and farm unoccupied territories.