Medieval Spanish empire

Imperator totius Hispaniae is a Latin title meaning "Emperor of all Spain". In Spain in the Middle Ages, the title "emperor" (from Latin imperator) was used under a variety of circumstances from the ninth century onwards, but its usage peaked, as a formal and practical title, between 1086 and 1157. It was primarily used by the Kings of León and Castile, but it also found currency in the Kingdom of Navarre and was employed by the Counts of Castile and at least one Duke of Galicia. It signalled at various points the king's equality with the Byzantine Emperor and Holy Roman Emperor, his rule by conquest or military superiority, his rule over several people groups ethnic or religious, and his claim to suzerainty over the other kings of the peninsula, both Christian and Muslim. The use of the imperial title received scant recognition outside of Spain and it had become largely forgotten by the thirteenth century.

The analogous feminine title, "empress" (Latin imperatrix), was less frequently used for the consorts of the emperors. Only one reigning queen, Urraca, had occasion to use it, but did so sparingly.

A surviving charter of 863 refers to Ordoño I as "our lord, residing in the Asturias" (domno nostro Ordonio residente in Asturias), qualifying him as a "commanding prince" (imperante principe). This residential form of title was preferred because the Asturian kingdom at this stage was not ethnically unified or well-defined.

There exist two diplomas dated to the reign of Alfonso III of Asturias and referring to him as emperor, but both are early twelfth-century fabrications emanating from the scriptorium of the Diocese of Mondoñedo and Bishop Gonzalo, designed to bolster that church's claims in a dispute of 1102. The first document, dated to 866 or 867, confirmed by Alfonso, who signs as "I, Alfonso, of all Spain emperor, who is unworthily permitted to be called the Catholic". The other refers to him simply as "Alfonso, Emperor of Spain" (Adefonsus Hispaniae imperator). The forger may have borrowed these exalted titles from the chancery of Alfonso VI, who was using the title imperator totius Hispaniae at the time. The subscription lists of both these charters (that is, the list of those who witnessed or confirmed them) are compatible with the dates, and it has been suggested that the clauses referring to Alfonso as emperor are derived from authentic (albeit now lost) charters.

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