Write five facts about the caliphs in short words

1. Caliphs were the successors of Prophet Muhammad and served as the spiritual and political leaders of the Islamic world.

2. The first four caliphs, known as the Rashidun Caliphs, were Abu Bakr, Umar, Uthman, and Ali.
3. They played a crucial role in the expansion of Islam, as the Arab armies conquered vast territories, including present-day Egypt, Syria, Iraq, and Iran.
4. Caliphs held significant religious authority, ensuring the spread of Islam and the codification of Islamic laws.
5. The Umayyad and Abbasid dynasties followed the Rashidun Caliphs, with the Islamic empire reaching its peak during the Abbasid rule.