Umar ibn al-Khattab, the second Caliph of the Rashidun Caliphate, was a transformative figure in Islamic history. Initially an opponent of Islam, his conversion marked a turning point. As Caliph, he expanded the Islamic empire and established a robust administrative system. His reforms in justice, governance, and military organization laid the groundwork for the Islamic Golden Age. Umar's legacy of humility and justice continues to inspire leaders today.