Portugal's main political rival during the period of 1450 to 1700 was Spain.
How did Portugal and Spain oppose each other ?
Portugal and Spain were both Iberian kingdoms that emerged during the Reconquista, the centuries-long struggle to expel Muslim Moors from the peninsula.
By the 15th century, both kingdoms had achieved territorial consolidation and were ready to expand their power beyond the Iberian Peninsula.
The rivalry between Portugal and Spain was also intense overseas, as both kingdoms competed for colonial territories and trade routes. Portugal established a vast empire in Africa, Asia, and South America, while Spain focused on the Americas and the Caribbean.