Salman the Persian

Salman Farsi (born Ruzbeh Khoshnudan; Persian: سلمان فارسی; Arabic: سَلْمَان ٱلْفَارِسِيّ) was a Persian religious scholar and one of the companions of Prophet Muhammad. As a practicing Zoroastrian, he dedicated much of his early life to studying to become a magus, after which he began travelling extensively throughout Western Asia to engage in constructive dialogue with non-Zoroastrian groups. His quests eventually prompted his conversion to Christianity and later his conversion to Islam, which occurred after he met and befriended Prophet Muhammad in the city of Medina. He was a prominent non-Arab companion and one of Prophet Muhammad's closest friends; Prophet Muhammad had once stated to a gathering of his followers that he regarded Salman as a part of his family. In meetings with the other companions, he was often referred to by the kunya Abu ʿAbdullah.

Prior to the Battle of the Trench in 627, Salman suggested to Prophet Muhammad and the other early Muslims that a large trench be dug around Yathrib (citing a technique commonly used by the Sasanian army) in order to help defend against the Quraysh, who were marching from Mecca in order to besiege the city. After Prophet Muhammad's death in 632, Salman became closely associated with Prophet Muhammad's cousin and son-in-law Ali ibn Abi Talib and is claimed to have participated in the Muslim conquest of Persia, aiding the territorial expansion of the Rashidun Caliphate outside of the Arabian Peninsula.