When Isabella defied her half-brother by secretly marrying Ferdinand in 1469, she set the stage for a united Spain and centuries of empire. The marriage of Isabella and Ferdinand united the crowns of Castile and Aragon. But it was Isabella's relentless drive that centralized power and launched the Spanish Inquisition in 1478. After the death of her predecessor Henry IV in 1474, Isabella fought a civil war to secure her claim. By 1479, she was undisputed Queen of Castile, a ruler determined to reshape the realm. Isabella’s Spain was not yet complete. For a decade, she waged the Reconquista to conquer Granada, the last Muslim stronghold. In January 1492, it fell, ending nearly 800 years of Islamic rule in Iberia. Three months later, Isabella signed the Alhambra Decree, ordering the expulsion of all Jews. That same year, she backed Christopher Columbus on his ambitious voyage westward. Isabella died in 1504, leaving a transformed Spain and a new world order. Her reign sparked the Spanish Empire, the Inquisition’s legacy, and a global encounter that still echoes. 📄 Image Credits All images via Wikimedia Commons:- Isabella I of Castile: https://commons.wikimedia.org/wiki/File:Juan_de_Flandes_-_Isabel_la_Cat%C3%B3lica_%28Palacio_Real%2C_Madrid%2C_1500-04._%C3%93leo_sobre_tabla%2C_63_x_55_cm%29.jpg See links for full license details. 🔔 Subscribe for more forgotten stories from history: [Your Channel Link] 💬 What do you think was Isabella’s most impactful decision? #history #chronology #ReyesCatolicos #Inquisition #medievalpower #IsabellaI #WarOfSuccession #15thCentury #ReconquistaEnd #FallOfGranada #1492 #AlhambraEdict #Columbus #1492Consequences #IsabellaLegacy #SpanishEmpire #HistoryDebate