Ferdinand II of Aragon vs Stefan Uros IV Dusan

Ferdinand II of Aragon married Isabella I of Castile in Valladolid, uniting the two largest Christian kingdoms in Spain. This marriage created the basis for the Kingdom of Spain, though both crowns remained legally separate until the death of Isabella in 1504.

Ferdinand II and Isabella I obtained papal approval to establish the Spanish Inquisition, a tribunal to enforce Catholic orthodoxy. The Inquisition targeted converted Jews (conversos) and Muslims (moriscos) suspected of secretly practicing their former religions, leading to thousands of executions and imprisonments.

Ferdinand II and Isabella I completed the Reconquista by capturing the city of Granada, the last Muslim stronghold in the Iberian Peninsula. The surrender of the Nasrid kingdom ended nearly 800 years of Muslim rule in Spain and marked a major victory for the Catholic Monarchs.

Ferdinand II and Isabella I issued the Alhambra Decree, ordering the expulsion of all Jews from the kingdoms of Spain who refused to convert to Catholicism. The decree led to the exile of an estimated 200,000 Jews, causing a significant demographic and economic impact on Spain.

Stefan Dušan was crowned Emperor (Tsar) of Serbs and Greeks in Skopje by the newly elevated Serbian Patriarch Joanikije II. This coronation asserted Serbian imperial ambitions over Byzantine territories. The act created the Serbian Empire, claiming succession to the Byzantine Empire and challenging Constantinople's authority.

Dušan convened a church council in Skopje that elevated the Serbian Archbishopric to a Patriarchate, with Joanikije II as the first Patriarch. This act was done without Constantinople's approval, causing a schism. The Serbian Patriarchate provided ecclesiastical independence for the empire and legitimized Dušan's imperial coronation.

Dušan's armies conquered most of Macedonia, including the cities of Serres, Drama, and Kavala, as well as Epirus and Thessaly. These conquests expanded the Serbian Empire to its greatest territorial extent, covering much of the Balkan Peninsula. The acquisitions gave Serbia access to the Aegean Sea and control over key trade routes.

Dušan issued the Zakonik, a comprehensive legal code consisting of 201 articles. The code regulated all aspects of society, including feudal relations, church rights, and criminal law. It was based on Byzantine law but adapted to Serbian conditions. The code remained in use until the Ottoman conquest and influenced later Balkan legal systems.

Dušan died suddenly at age 47, possibly from poisoning or illness, near Constantinople while preparing a campaign against the Byzantine capital. His death left the Serbian Empire without a strong successor. His son Stefan Uroš V proved unable to control the nobility, leading to the empire's fragmentation into rival principalities within two decades.