Abu Bakr vs Isabella I of Castile

Abu Bakr launched military campaigns against Arabian tribes that renounced Islam or refused to pay zakat after Muhammad's death. The wars, led by generals like Khalid ibn al-Walid, reestablished Muslim control over Arabia and consolidated the caliphate.

After the death of Muhammad, Abu Bakr was elected as the first caliph (successor) at Saqifah. His election unified the Muslim community, though it caused controversy among some supporters of Ali. He became the leader of the nascent Islamic state.

Abu Bakr ordered the compilation of the Quran into a single written manuscript after many memorizers died in the Ridda Wars. Zayd ibn Thabit collected verses from various sources, creating the first official codex, which later served as the basis for Uthman's standard text.

Abu Bakr died after a brief illness, having designated Umar as his successor. His caliphate lasted only two years but established the foundations of the Islamic state, including the expansion beyond Arabia and the preservation of the Quran.

Isabella married Ferdinand II of Aragon in Valladolid, uniting the kingdoms of Castile and Aragon. This dynastic union laid the foundation for the unified Spanish monarchy and enabled joint policies including the Reconquista and overseas exploration.

Isabella obtained papal approval to establish the Spanish Inquisition in Castile, aimed at maintaining Catholic orthodoxy among converted Jews and Muslims. The Inquisition operated under royal control, conducting trials and executions for heresy.

Isabella and Ferdinand completed the Reconquista by capturing the Nasrid kingdom of Granada. The surrender of the last Muslim state in Iberia ended 781 years of Islamic rule and unified Spain under Christian rule.

Isabella and Ferdinand issued the Alhambra Decree ordering the expulsion of all Jews from Spain who refused conversion to Catholicism. An estimated 40,000 to 200,000 Jews were forced to leave, causing demographic and economic disruption.

Isabella agreed to fund Christopher Columbus's expedition across the Atlantic, providing three ships and supplies. Columbus reached the Bahamas on October 12, initiating sustained European contact with the Americas and the Spanish colonial empire.

Isabella and Ferdinand negotiated the Treaty of Tordesillas with Portugal, dividing newly discovered lands outside Europe along a meridian 370 leagues west of the Cape Verde islands. This agreement shaped colonial claims in the Americas and Africa.