The Ayyubid Sultanate was a medieval Muslim state founded by Salah ad-Din (Saladin) in the late 12th century. It emerged in response to the Crusades and expanded across parts of the Middle East, including modern-day Egypt, Syria, and Yemen. The Ayyubids are known for their military prowess and efforts to unite Muslim territories against the Crusaders. The Ayyubid dynasty lasted until the 13th century, when it began to decline due to internal strife and external pressures, including the rise of the Mamluks. The Ayyubids contributed to Islamic culture, architecture, and scholarship, leaving a lasting legacy in the regions they ruled.