Islam in China
Sa'd ibn Abi Waqqas, along with three Sahabas, namely Suhayla Abuarja, Uwais al-Qarani, and Hassan ibn Thabit, returned to China from Arabia in 637 by the Yunan-Manipur-Chittagong route, then reached Arabia by sea. Some sources date the introduction of Islam in China to 650 AD, the third sojourn of Sa'd ibn Abi Waqqas, when he was sent as an official envoy to Emperor Gaozong during Caliph Uthman's reign.