In the 10th century all of Spain was under the control of the Islamic Caliphate of Cordoba, with the exception of the northern Kingdoms of Asturias and Navarre and the Spanish March. Sancho III of Navarre united the greater parts of these realms in the early 11th century, but upon his death his kingdom was split between his sons into Navarre, Aragon, and Castile. Castile soon merged with the Kingdom of León in the northwest of Spain, while Aragon and the county of Catalonia eventually merged in the east. Meanwhile the caliphate in the south had collapsed, and Castile and Aragon expanded their borders south until in 1248 the only Muslim possession in Spain was Granada (which lasted until 1492).
Castile and Aragon were united as Spain in 1479 when the husband and wife team of Fernando III of Aragon and Isabel I of Castile ascended the thrones. After their deaths the crown of Spain went to their grandson Carlos (the Holy Roman Emperor Charles V), a Habsburg, who also possessed extensive territories in Austria. Spain was ruled by the Spanish Habsburgs until 1700, at which time occurred the War of the Spanish Succession and the installment of a French Bourbon king, Felipe VI, as the ruler of Spain.
The monarchy was absent in Spain from 1808 to 1814 (as a result of Napoleon), and from 1931 to 1975.
Spanish Kings and Queens Chronologically
Spanish Kings and Queens by Frequency of Name
Spanish Kings and Queens Alphabetically (Grouped by Name)