Final answer:
Portugal colonized Brazil primarily for economic reasons, particularly for dyewood trade and later discovering gold and diamonds. Moreover, the expansion of Christianity also played a large role.
Step-by-step explanation:
The main motive that led to the colonization of Brazil by Portugal was primarily economic in nature. The Portuguese had learned of the lucrative trade in dyewood, a high-quality wood used in the textile industry, that could be cut along the Brazilian coast. This eventually pushed the said monarchs to claim lands in South America in order to exploit this resource.
Moreover, they were also interested in finding a route to Asia for the spice trade and saw the colonization as an opportunity to establish a base on the continent. However, they did not find a route but they instead found vast quantities of gold and diamonds in the territory later which further intensified their exploitation.
The expansion of Christianity also had its part to play in the colonization efforts. The Portuguese, being staunch Roman Catholics, believed in religious propagation and converting the natives to their faith.
So the final answer in two lines is: The colonization of Brazil by Portugal was chiefly fueled by a combination of the quest for commercial opportunities in textile and later, in mining gold and diamonds, as well as religious motives.
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