Was Suhayb ibn Sinan called "Suhayb ar-Rumi" because he was a Roman?

Suhayb (may Allah be pleased with him) was not Roman; rather, he was an Arab from the clan of Namir ibn Qasit. The reason he was called "Ar-Rumi" (the Roman) is that he was captured as a child by the Romans, so he learned their language.