How did Spain come to share its monarch with half of Europe? The accession of Charles I to the throne transformed Spain's position in the world, but not necessarily for the better. Consumed by his other responsibilities as Holy Roman Emperor, Charles was often absent from Spain, breeding domestic issues and resentment in the early years of his reign.

But who was Charles I of Spain and how did he amass such great responsibilities? Charles I followed on from the Catholic Monarchs Ferdinand II and Isabella I to rule Spain in 1516. He is often, however, more frequently referred to by his other title of Holy Roman Emperor (Charles V). To understand how he came to be both King of Spain and Holy Roman Emperor, we need to explore his familial history.

How did Charles I become King of Spain?

Charles I was born in 1500 to Philip I (known as Philip the Handsome) and Juana of Castile. Their marriage was strategic. Philip’s parents were Mary, Duchess of Burgundy and the Holy Roman Emperor and King of Germany, Maximilian I. Juana was the daughter of King Ferdinand II and Queen Isabella I of Spain. Charles, as a result, was born to inherit all these titles.

Charles I's family tree showing the titles he inherited

He grew up in the Netherlands, which formed part of the Imperial and French fiefs, known as the Burgundian Netherlands. In 1515, he became the Duke of Burgundy and assumed rule over this area. When Ferdinand II died a year later in 1516, Charles inherited his rule over Spain, becoming King Charles I of Aragon and Castile.

His power expanded immensely when his grandfather, Maximilian I, died in 1519, leaving his titles of the Archduke of Austria, King of Germany, and Holy Roman Emperor for Charles to inherit.

Balancing this vast amount of power made it very difficult for Charles to focus on one country, making him a perpetual absentee monarch. As part of the Habsburg Dynasty, his primary focus was on maintaining their power and fighting the Holy Roman Empire’s battle against Protestantism and the Ottoman Empire.

Charles’ titles

Here is a list of all the titles that Charles I had or inherited when his father died.

• Duke of Burgundy, Lord of the Netherlands (1506–55)

• Charles I, King of Spain (1516–56)

• Charles I, Archduke of Austria (1519–21)

• Charles V, King of Germany and Holy Roman Emperor (1519–56)

Within Spain, he also became the King of both Aragon and Castile, finally uniting the two kingdoms that were still separate under Isabella and Ferdinand.

What opposition did Charles I face in Spain?

Charles I experienced opposition in Spain from the very beginning of his rule. His childhood in the Netherlands meant he lacked knowledge of the Spanish language or customs, which immediately established him as an outsider. Distrust evolved into active opposition and resulted in several crises for Charles to tackle in his early years as the Spanish King.

Succession

Charles was proclaimed joint ruler with his mother Juana in Brussels in 1516, and he travelled to Spain a year later. Whilst Charles was named in Ferdinand’s will as ruler, many Castilians (including Ferdinand) preferred his brother Infante Ferdinand as the heir to the throne. He had been born in Spain and enjoyed strong support amongst the group that later joined the Comunero Revolt. Charles had a simple solution to this initial issue: he sent his brother to Germany and thus eliminated the threat of a succession war.

Revolt of the Comuneros

Charles was crowned Holy Roman Emperor in 1519, left Spain for Germany, and installed Pope Adrian VI as his regent in Spain. In 1520, growing discontent with Charles I and his administration erupted into an uprising by the citizens of Castile, known as the Revolt of the Comuneros. Castilian elites wanted more power in government and feared the Dutch influence that Charles I brought. Pope Adrian VI was not strong enough to suppress the rebels, and during the height of the rebellion, they succeeded in controlling the cities at the heart of Castille.

Suppression of the Revolt

Royal forces eventually suppressed the revolt in 1521, but it was not necessarily a defeat for the rebels. Charles positioned many of the Castile elite in government, removing unpopular, ineffective, and corrupt officials. The Revolt also encouraged Charles to return to Spain in 1522, where he stayed for the next seven years, building better relations with the Castilians, and settling the government of the country.

Historian Henry Kamen argues that this period was

Painting of the Revolt of the Comuneros.

Revolt of the Germanías (Revolt of the Brotherhoods)

Another revolt in Valencia took place in 1519–23, parallel to the Castile rebellion. Valencia had plunged into a severe economic crisis due to reduced trade. Europe’s focus on discovery in the Atlantic Ocean meant that Valencia’s artisan guilds (known as Germanías) were neglected and unable to make as much money. They could not generate money through Atlantic trade as Valencia had been excluded from participating in the cross-Atlantic trade.

The guilds rebelled against King Charles, fighting against monarchy and feudalism, the nobility that had fled Valencia after the plague broke out in 1519, and against the Muslim population of Aragon.

Repression of the Revolt

The protest was brutally repressed by Germaine de Foix, widow of Ferdinand II and newly appointed Vicereine of Valencia. She treated the rebels harshly, condemning hundreds to the death penalty and issuing huge fines. These actions quelled resistance and helped Charles gain authority. His popularity grew so much that when he visited the city in 1527, a bridge collapsed due to the enormous crowds that had come out to see him.

Portrait of Germaine de Foix.

What was Spain like under Charles I?

As we've seen, Charles of Spain's reign was difficult and faced opposition. Now we will focus on how his rule was organised and how the country was administered.

An absentee Monarch

Charles’s imperial commitments meant he was often needed in other countries. During his reign, he travelled to Germany, Spain, Italy, France, the Netherlands, England, and Africa for duties. These obligations meant he was rarely in Spain. In 1529, he left his wife Isabella of Portugal in charge of Spain as regent, acting under the advice of the Archbishop of Toledo, president of the council of Castile.

Isabella died in 1539, and the regency was passed to his son Philip a few years later in 1543. Charles left Philip specific instructions, which he followed devotedly and continued into his own reign.

The Cortes

Under Charles, the Cortes (courts) asked him to hold public court on specific days of the week to dispense royal justice. Ferdinand II and Isabella I had done this before him and kept it a modest affair. However, Charles took a far more lavish and complex approach and convened the courts sporadically when he returned to the country.

Administration

Charles, like Ferdinand and Isabella, chose Castile as the centre of his administration and made several innovations. He set up a council of state in 1526 to discuss the most important matters concerning Spain and Germany. He rarely used it, but it became the supreme organ of government after his abdication.

In 1523, Charles’s chancellor Mercurino de Gattinara created a new council of finance called the Hacienda. It managed the finances of Castile and the accounts of most of the economy.

Francisco de los Cobos, Charles' secretary of state, handled the Spanish administration during Charles’s reign. He recruited and trained bureaucracy for the local government in Castile and dedicated his time to focus on Spanish internal affairs whilst Charles was absent.

What was Charles I’s foreign policy?

Charles inherited a legacy from his grandfather Maximilian I that was hard to live up to. The historian Thomas A. Brady Jr. described Maximilian as the

During Charles I’s reign, he continued Maximilian’s foreign policy and was almost constantly engaged in conflicts.

Habsburg dynasty

Charles, as a member of the Habsburg dynasty, focused his foreign policy on protecting and expanding their power. The dynasty had two main enemies that threatened its power:

• The Ottoman Empire: a Turkish dynasty that controlled most of southeastern Europe, Northern Africa, and Western Asia.

• The Valois Dynasty: a French dynasty that worked towards unifying France.

Charles engaged in several conflicts against these two powers referred to collectively as the Ottoman-Habsburg Wars and the Habsburg-Valois Wars.

Key Foreign Conflicts

• The Italian Wars (1521–26; 1526–30; 1542–46; 1551–59): the Italian Wars, sometimes referred to as the Valois-Habsburg Wars, were a series of conflicts fought between the Habsburg and Valois monarchies in Italy.

• Conquest of Tunis (1535): Charles and the Habsburg Empire successfully captured Tunis (in Modern Tunisia) from the Ottoman Empire.

• Algiers Expedition (1541): Charles attempted to lead an attack against the Ottoman Empires’ stronghold of Algiers (in modern Algeria) but failed due to poor planning and bad weather. His efforts to conquer North Africa thus failed.

• Schmalkaldic Wars (1546–47; 1552): Charles fought wars against the Lutheran Schmalkaldic League (Lutheran Princes) to prevent areas of Germany from becoming Protestant.

How did the Spanish Empire expand under Charles I?

Whilst Columbus had made the initial discovery of America, Cortés’ and Pizarro’s discoveries of Mexico (1519) and Peru (1526) in the early years of Charles’s reign had far more of a profound impact on Spain’s power and wealth. During this period, Spain’s influence extended vastly, and new treasures were found that enriched the economy.

Although it took a long time to establish rule in these new territories (1553 in Mexico and 1551 in Peru), their colonisation resulted in a great expansion of power for Spain and the potential for wealth, which was an important accomplishment for Charles. However, Charles I’s foreign wars across the Holy Roman Empire meant that most of the bullion extracted was frittered away on imperial armies. Spain itself suffered from inflation and royal debt rather than enjoying a wealthy society. The funding of the military would, however, establish Spain as an emerging military power.

Imperial versus Spanish interests

Not all imperial pursuits corresponded with Spanish interests. The wars against the Valois Dynasty continued Spain’s disputes with France but the war against Protestantism in Germany and conflicts against the Ottomans on the other side of Europe held little value for Spain itself. Spaniards were critical of Charles’ foreign policy, especially as the wars were costly and Charles used Spanish funds to support them. Spain's economy and population paid the price as Charles used heavy taxation and the wealth gained from the exploration in the Americas to fund these wars.

Religion during Charles I’s reign

Charles continued the Spanish Inquisition started by his grandparents, the Catholic Monarchs, forcing Jews and Muslims to convert to Christianity. But during his reign, a new threat to Catholic dominance emerged: Protestantism.

The Spanish Inquisition and the rise of Protestantism

The Spanish Inquisition continued during Charles’s reign and the persecution accelerated. Muslims in Valencia and Aragon were forced to convert to Christianity in 1526 and Islam was later banned in Spain.

During Charles’ reign, a new threat emerged. Protestantism’s popularity was growing throughout Europe and appealing to those disillusioned with Catholicism. In 1521 Martin Luther, a founder of Protestantism, refused to recant his beliefs at a meeting with Charles about his heresy called the Diet of Worms. Rather than deter others from converting to Protestantism, his speech at the Diet inspired many followers.

For Charles, Protestantism posed a serious threat to the Catholic kingdoms. He unsuccessfully attempted to introduce the Spanish Inquisition in the low countries to eradicate it. He ultimately failed to contain Protestantism despite all his efforts.

Charles I’s accomplishments and failures

You might be asked to argue the extent to which Charles established a stable government and demonstrated strong leadership during his reign. When answering, you need to discuss the accomplishments and failures of his reign and come to your own conclusions. Here are some accomplishments and failures to think about.

Charles I’s abdication

Charles I's failures and health problems led him to abdicate in 1555. He left his titles in the Netherlands and Spain to his son Philip II and the title of emperor to his brother Ferdinand. He then retired to a monastery where he would die in 1558.

Philip II was crowned the King of Spain in 1556. The Spain he inherited was peaceful thanks to his father's accomplishments.

1. Henry Kamen, Spain, 1469-1714: A society of conflict, 2005.