section_path: History/Islam
section_name: Islam
paragraph_text: Islam
  
  The spread of Islam to the northeastern tip of the Arabian Peninsula is thought to have followed directly from a letter sent by the Islamic prophet Muhammad to the rulers of Oman in 630 CE. This led to a group of rulers travelling to Medina, converting to Islam, and subsequently driving a successful uprising against the unpopular Sassanids, who dominated the coast at the time. Following the death of Muhammad, the new Islamic communities south of the Persian Gulf threatened to disintegrate, with insurrections against the Muslim leaders. Caliph Abu Bakr sent an army from the capital Medina which completed its reconquest of the territory (the Ridda Wars) with the Battle of Dibba in which 10,000 lives are thought to have been lost. This assured the integrity of the Caliphate and the unification of the Arabian Peninsula under the newly emerging Rashidun Caliphate.
  
  In 637, Julfar (in the area of today's Ras Al Khaimah) was an important port that was used as a staging post for the Islamic invasion of the Sasanian Empire. The area of the Al Ain / Buraimi Oasis was known as Tu'am and was an important trading post for camel routes between the coast and the Arabian interior.
  
  The earliest Christian site in the UAE was first discovered in the 1990s, an extensive monastic complex on what is now known as Sir Bani Yas Island and which dates back to the seventh century. Thought to be Nestorian and built in 600 CE, the church appears to have been abandoned peacefully in 750 CE. It forms a rare physical link to a legacy of Christianity, which is thought to have spread across the peninsula from 50 to 350 CE following trade routes. Certainly, by the fifth century, Oman had a bishop named John – the last bishop of Oman being Etienne, in 676 CE.