The early caliphates and the spread of Islam

By the time of Muhammad’s death in 632 CE, Muslim forces had invaded the southern parts of the Persian Empire. They also successfully invaded Byzantine territories in Syria, Palestine and Egypt. When Muhammad died, his successor was Abu Bakr; his Rashidun Caliphate expanded into central Asia and North Africa. Captured cities were often treated well; in Damascus the Christian people were not hurt and allowed to worship freely. The caliph Umar captured Jerusalem in 638 CE; it is the third holiest city to many Muslims.