Hazrat Hafsa bint Al-Umer was the daughter of the second caliph, Hazrat Umer bin Khattab. She married Khunais bin Huzaifa and became Muslim along with her parents and husband. After Khunais was martyred in the Battle of Badr, the Prophet Muhammad expressed his desire to marry Hafsa, making her his fourth wife. As the wife of the Prophet, Hafsa served Islam by transmitting hadith, guarding the original manuscript of the Quran, and demonstrating great religious knowledge and devotion to prayer and fasting. She died in 45 A.H. during the caliphate of Muawiya.