Salman was born in Persia, in a family of fire-worshippers. He himself related how he left home in search of the truth, served scholars from one city to another, and how the last of them told him that the final prophet would appear in a land of date palms in Arabia.
❝ HadithBetrayed on the way, he was sold as a slave and came, as it happened, to Madinah — that land of palms. When the Messenger of Allah ﷺ arrived after the Hijrah, Salman went to him, checked the signs the scholar had described, and accepted Islam. Later, with the Prophet's ﷺ guidance and the Companions' help, he paid his ransom and was freed.Musnad Ahmad 23737 · Hasan
The histories record that at the Battle of the Trench, the idea of digging a trench to defend Madinah came from him.
ⓘ The account of Salman's journey is in Musnad Ahmad in his own words; hadith scholars graded its chain hasan. The trench is mentioned in the Sirah works.