Final answer:
Portugal established a maritime empire focused on controlling nautical trade routes and establishing trading posts.
Step-by-step explanation:
The empire established by Portugal was a maritime empire. Portuguese mariners built an Atlantic empire by colonizing islands such as the Canary, Cape Verde, and Azores Islands. They also established trading posts in China, Japan, and along the western coast of Africa and India. Portugal's empire was primarily focused on controlling nautical trade routes and establishing trading posts.