Which country was primarily involved in the early Atlantic slave trade?

The primary country involved in the early Atlantic slave trade was Portugal. In the 15th century, Portugal became a pioneer in establishing trade routes along the West African coast. The Portuguese were among the first Europeans to engage in the transatlantic slave trade, taking enslaved Africans to their colonies in the Americas, particularly in Brazil, as well as to other locations.

Portugal's involvement in the slave trade was driven by economic interests, as they sought labor for their sugar plantations. This system expanded rapidly, leading to significant demographic and cultural changes in the Americas and contributing to the development of the plantation economy.

The extensive maritime experience of the Portuguese, coupled with their early colonization efforts, positioned them to dominate the slave trade during its initial phases, before other European nations, such as Spain, France, and Great Britain, became heavily involved in the 17th and 18th centuries. Thus, Portugal's critical role in this historical context makes it the correct answer to the question about early involvement in the Atlantic slave trade.