Answer:
3- Iberia was often under the control of other empires
Explanation:
The Iberian Peninsula is the western border of the Mediterranean region, thus it has been involved in the happenings of this region since ancient times. There was no strong civilization on this peninsula, so the other civilizations took advantage of it. The Phoenicians (also called Carthaginians later in the history) and the Ancient Greeks made colonies along the eastern coast and didn't really had any big troubles in maintaining them. After that is was the Romans that came and invaded, putting the peninsula under their control. With the spreading out of the Islamic Caliphates, part of the peninsula was invaded by the Muslims, and it was occupied for few centuries. It was only when the Spanish crown was established that the Iberian Peninsula got a strong native country that soon became a global force.