When did Spain become a single kingdom?

First, an analogy with the U.K.: In 1603, King James VI of Scotland succeeded to the English throne, uniting the crowns of England and Scotland in a single person. However, England and Scotland remained separate kingdoms, with their own laws and parliaments, until 1707, when the Act of Union created the single unified Kingdom of Great Britain.

Similarly, in Spain, the crowns of Aragon and Castile were united through the marriage of Ferdinand and Isabella. Ferdinand succeeded to the throne of Aragon (and later Navarre), Isabella succeeded to Castile, and their descendants beginning with their grandson Charles I inherited all of the crowns together. However, at that time the kingdoms remained independent, with their own laws and “cortes” or Parliaments (roughly equivalent to the British House of Lords).

When were the kingdoms unified?. Spain today is a single nation with a single Parliament, and regional governments that are subordinate to the federal government. When did this happen? I can’t find any history book that gives the answer. Does anybody know?

Oddly enough, the main step towards unification almost coincides with the Anglo-Scottish union of 1707. Indeed, one could argue that both were by-products of the War of the Spanish Succession - Spanish unification more obviously so than British unification. The separate administrations for Castile, Aragon and Valencia were abolished by Philip V in 1707 and a cortes representing most of Spain met for the first time in 1709.

Yup, with the new king of the house of Bourbon Spain was unified into a more centralised system similar to the French Monarchy.

Yeah, the Bourbons were heavy on the uniform centralization.

But even then, and going back all the way to the early medieval kingdoms, there was all along the tradition of the fueros, legal arrangements under which communities within the kingdoms retained their ancestral locally-applicable laws and institutions, often overriding central edicts. This was a source of unending stress not just for the old Bourbons but even for the earlier Hapsburgs and the rulers of the late medieval kingdoms. Plus of course you had the reality of distinct actual nations like Basques within your borders.

Hardliners among the Bourbons in the 18th-19th centuries, and the Nationalists in the 20th, attempted to suppress the fueros and the distinct identities of the components of Spain, viewing them as a source of division and dissent. Franco was specially fierce about it. During most of the 20th century, Spain was a unitary state with many relatively small city-centered provinces with little local autonomy.

In the end, they could not erase the regional identities or the concept of the fuero. When the monarchy was restored, the current federative-style arrangement, where the “states” have a healthy degree of autonomy and are roughly based on the ancient kingdoms (Asturias, Navarre, Catalunya, Aragon, Euskadi, Castilla-Leon, Galicia, etc.) was adopted.

>> This was a source of unending stress not just for the old Bourbons but even for the earlier Hapsburgs and the rulers of the late medieval kingdoms.

In the 16th - 17th centuries Castile was much more powerful & richer than Aragón and so, had more weight. The King had more power in Castile and the Cortes were much more subservient to him. OTOH, in Aragon there was much less centralism and there were different Cortes for the different kingdoms (although they customarily met together for convenience). These Cortes retained a greater degree of autonomy and power. The kings soon got tired of having to spend so much energy on Aragon to get much less in return and so dedicated most of their attention to Castile (and the New Indies). This, in turn, alienated the people of Aragon who felt the king did not give them attention.

There is an interesting incident in the story of the secretary Antonio Perez, secretary of king Philip II who was imprisoned by the king in Madrid and escaped. After riding all night he made it to the line of Aragón and knew he was safe as now he would have to be legally extradited first. The King demanded the extradition to castile but Antonio Perez managed to inflame the people of Zaragoza into believeing this was an affront to their rights. There was much legal wrangling between the Justicia Mayor who represented the kingdom of aragon and the Viceroy who represented the king. Time passed and the situation was getting more and more heated. Finally the viceroy was ordered to disregard legal niceties and take Antonio Perez but the people of Zaragoza revolted killing the viceroy and Antonio Perez escaped to France where he finished his days. Soon later the Castilian armies entered Aragón and restored “order” with exemplary punishments. The fueros were respected but the incident weakened the position of Aragon and prepared the abolition of the fueros by Philip V.

This is a fascinating story which shows, among other things, the great respect for the ruel of law in Spain at that time where not even the king himself was above the law, on the contrary, he was very much limited by the law. The trend with the Bourbons was towards absolute power and this was quite negative in a country which had a tradition of giving the kings very limited powers.

The king was considered to be “primus inter pares” rather than absolutely above the nobility. An example of this is the formula the nobles of Aragón used to swear allegiance to the new king and which went something like this: “We, who are worth as much as you, and united more than you, swear allegiance to you as long as you abide and respect our laws and privileges, our uses and our customs”. The cortes of Aragón always made the king feel like he had to beg and the king hated that and tried to get by without conveneing them. . . but he could not impose taxes without the authorization of the Cortes so if he wanted money he had to beg.

The Cortes of Castile were much more docile but even in Castile the people got fed up in times of his father the emperor Charles and it ended up in a civil war (guerra de las comunidades o comuneros).

At any rate, Spain under the Hapsburgs had a political organization and a respect for the rule of law which was unprecedented and way ahead of its time. After 1700 though, Spain deacys quite fast and the centralism and absolutism of the Bourbon kings did not help at all