The "Meccan period" refers to the early phase of the life of the Prophet Muhammad before he migrated to Medina. This period lasted from his birth in 570 CE until 622 CE and is characterized by his early teachings and the initial spread of Islam. During this time, Muhammad preached monotheism and social justice, often facing opposition from the powerful tribes of Mecca. The Meccan period is significant for the revelation of many verses of the Quran, which addressed issues of morality, ethics, and community. The growing number of followers faced persecution, leading to a pivotal moment in Islamic history when Muhammad and his followers eventually migrated to Medina, marking the beginning of the Islamic calendar.