They functioned as homes and regional capitals for governmental figures throughout the Umayyad caliphate and later, for Christian rulers following the Spanish Reconquista.

The term alcázar is also used for many medieval castles built by Christians on earlier Roman, Visigothic or Islamic fortifications and is frequently used as a synonym for castillo or castle.

The Spanish word alcázar derives from the Arabic word القصر al-qaṣr “the fort, castle, or palace,” that in turn derives from the Latin word Castrum (“fortress”, “military camp”).

Similar words exist in Galician, Portuguese, and Catalan.

Spain also has Muslim citadels known as alcazabas. However, not all castles in Spain are called alcázar: the majority are called castillo in Spanish or castell in Catalan.

Nor was every alcázar or alcazaba in Iberia built by the Muslims: many castles with these names were built after the Islamic caliphate was expelled from the Iberian Peninsula. Following the Spanish Reconquista, Christian patrons built or refurbished palaces to resemble the Islamic style, known as Mudéjar.

Often, alcázars are described as “Moorish,” a term used by Europeans to refer to followers of the Islamic faith. While “Moors” has been used for centuries to reference Spanish Muslims, today however, the discussion of “Moorishness” is often approached with care. The term has been radicalized historically in Spain to signify the Other and exoticize the Muslim population.

Modern language utilizes the terms Islamic, Muslim, and Andalusi instead of Moorish, but it is worth clarifying the historical context.

Alcázars were owned by Islamic, and later, Christian rulers of al-Andalus, the buildings symbolized the ruler’s power and wealth over the region. Over time, the different cultural influences of the buildings merged, marking the Alcázar as a transmission among Islamic, Christian and Jewish cultures.