Islam began in the 7th century in the Arabian Peninsula founded by the prophet Muhammad. The religion is based on revelations received by Muhammad which are recorded in the Quran. After Muhammad gained followers, Islam rapidly expanded through military conquest and conversion. As it spread, Arabic language and culture also spread while mixing with local cultures. Soon after Muhammad's death, the Sunni and Shia branches developed due to conflicting ideas about leadership. Over subsequent centuries, Islamic civilization expanded across large regions and was influenced by and influenced local cultures.