Pope Sixtus I (42 – 125), of Greek descent, was the Bishop of Rome from c. 115 to his death c. 125. He succeeded Pope Alexander I and was in turn succeeded by Pope Telesphorus. In the oldest documents, Xystus (from the Greek word for "polished") is the spelling used for the first three popes of that name. Pope Sixtus I is also the sixth Pope after Peter, leading to questions...