Why Spain Never Conquered Portugal – The Reasons

Portugal is basically stuck between the Atlantic on one side and Spain on the other side. And yet the much larger Spain has never conquered Portugal. But why did Spain never conquer Portugal?

Portugal and Spain fought in the Reconquista, military campaigns aimed at conquering the Muslim-controlled lands on the Iberian Peninsula. Portugal finished that process in 1249, and Spain in 1492. So until 1492, Spain was busy with conquering Muslim lands and had neither the interest nor the resources to conquer Portugal. In the Age of Discovery Portugal and Spain were rivals but now it was all about securing as much land overseas as possible instead of expanding the realms on the European continent.

Let`s take a closer look.

A brief history of Portugal & Spain from the Romans to the Age of Discovery

But to understand exactly why Spain never invaded Portugal we first have to take a brief look at the Iberian Peninsula and the development of both Portugal and Spain.

The Romans had already occupied the Iberian Peninsula during the Expansion of the Roman Republic and had split it into several provinces. In 197 BC, Rome first split Hispania (the Iberian Peninsula) into two provinces. Hispania citerior (the east of the Iberian Peninsula) and Hispania ulterior (the south and west of the Iberian Peninsula). The North of the Iberian Peninsula was still unconquered and the division into two provinces was kept until the time of Caius Julius Caesar.

After the fall of the Western-Roman Empire, the Visigoths (a Germanic tribe) ruled over the Iberian Peninsula under the name of „Regnum Gothorum“ (Kingdom of the Goths) from the 5th to the 8th century.

But their rule came to an end when Tariq ibu Ziyad, a Muslim Berber from North Africa invaded the Iberian Peninsula in 711 AD and conquered it piece by piece from the Visigoths. Here you can find out more about the Umayyad conquest of Hispania and the Muslim expansion in the Early Middle Ages in general.

As a result of the Umayyad invasion, almost the entire Iberian Peninsula (now called al-Andalus) fell under Muslim control (although Christians and Jews continued to live there in relative peace under the new Muslim rule).

In 1129 the county of Portugal (basically the North of today’s Portugal) started to gradually reconquer the territories of the different Muslim principalities in the Southern part of today’s Portugal. That process was mostly completed in 1249 when Alfonso III of Portugal was crowned. He was the first king who was crowned as king of Portugal and the Algarve (basically all of today`s Portugal)

So Portugal had already finished its Reconquista in 1249. But Spain hadn`t. The history of the Reconquista in Spain (or better the kingdom of Castille and the Kingdom of Aragon) is a highly interesting and complicated story, but also a story for another time.

Most important for our question of why Spain never invaded Portugal is, that Spain only finished the Reconquista in 1492 when the Emirate of Granada, the last Muslim principality on the Iberian Peninsula, was captured by Castilian troops.

By the way, even during the Reconquista the king of Castille had enlisted a bodyguard made up of Moorish knights. But that is a story for another time.

Let`s now look at how the history of the Iberian Peninsula helps us in answering the question of why Spain never invaded Portugal.

Why did Spain never conquer Portugal?

As mentioned, Spain was busy fighting in the Reconquista until 1492. That meant that before 1492 the Spanish resources were focused on conquering the Muslim-controlled parts of the Iberian Peninsula. During that time Spain simply didn`t have the interest or the resources to also conquer Portugal.

And after Christopher Columbus discovered the New World in 1492 (the same year the Reconquista ended for Spain), both Spain and Portugal focused their efforts on claiming as much of the New World (the Americas) as possible. However, that was also the time when Portugal and Spain rivaled each other over the control of the New World.

From 1492 onwards it was no longer the goal of Spain or Portugal to expand their realms on the European continent. Instead both countries wanted to claim as much land in the newly discovered world as possible.

So in 1494, the Treaty of Tordesillas was signed by Castille (basically Spain) and Portugal under papal mediation. The Treaty of Tordesillas (1494) divided the world into a Portuguese and a Spanish sphere of influence and a borderline along a meridian 300 leagues west of the Cape Verde Islands was agreed upon. Portugal got everything east of the borderline (including Brazil) while Spain got everything west and the concession that their ships could cross Portuguese waters unharmed.

So after the Reconquista had ended for Spain in 1492, Spain simply had no interest in conquering Portugal since claiming lands in the newly discovered Americas was much more profitable. So all forces were focused on claiming as much of the newly discovered world as possible.

However: Between 1580 and 1640 Portugal actually came under the rule of the Spanish Habsburg kings Philipp II, Philipp III, and Philipp IV. The reason for the so-called Iberian Union was that the Portuguese royal family had died out so the rule over Portugal came to the Spanish Royal family because of a loose degree of kinship.

Even when Spain and Portugal formed the Iberian Union (1580-1640) and the Spanish kings ruled over Portugal, that control had not been archived by Spain conquering Portugal but by receiving the rule over Portugal because of a loose degree of kinship with the Portuguese Royal family, that had died out.

And even when Portugal managed to regain its independence in 1640, Spain had still more lucrative targets in the New World so conquering Portugal and bringing it back into the Iberian Union was once again not among the Spanish goals.

So these are the reasons why Spain never conquered Portugal.

Spain was busy pushing the Muslims out of the Iberian Peninsula until 1492. And as soon as that was archived, Christopher Columbus discovered America and opened up a new world with incredible riches. So from then on Spain was interested in claiming as much of the new world as possible and conquering Portugal was once again not a goal since there were other, more lucrative targets.

Speaking of the Age of Discovery and the Spanish conquest of the New World. The Spanish explorers who made it to the Caribbean soon faced a serious problem: Their ships were basically falling apart in no time. Here you can find out what caused that and how the Spanish ships were maintained to prevent them from rotting.

Take care of yourself because you deserve it. You really do.

Until next time

Yours truly

Luke Reitzer


Joseph F. O`Callaghan: Reconquest and Crusade in Medieval Spain (Pennsylvania 2004).*

Charles Kovacs: The Age of Discovery (2004).*

A.R. Disney: History of Portugal and the Portuguese Empire. Vol. 1: From Beginnings to 1807 (Cambridge 2009).*

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