Why wasn’t Portugal conquered by Spain?

Why wasn’t Portugal conquered by Spain? ♦Consider to Support the Channel of Patreon and gain cool stuff: ♦Please consider to SUBSCRIBE : ♦Narrated by: Royal Carter ♦Music Used : Kevin MacLeod - Drums of the Deep Kevin MacLeod - BTS Prolog Nomadic Sunset by Alexander Nakarada @ SerpentSound Studios Lord, Have Mercie by Karstenholymoly ♦Sources : Parker, Geoffrey - The Spanish Armada Stanley G. Pay