Sixtus I was pope for about ten years, from 115 to 125. The Vatican's "Annuario Pontificio" ( 2003) identifies him as a Roman who reigned from 117 or 119 to 126 or 128. He is often commemorated as a martyr, like many of his predecessors in the papacy, though there is no historical foundation for such a belief. His successor Telesphorus is the first whom the writer Irenaeus designates a martyr.
