Pope Sixtus I, also known as Sixtus the First, served as the Bishop of Rome from around 115 to 125 AD. He is recognized as the sixth pope in the history of the Catholic Church and is believed to have succeeded Pope Anacletus. His papacy occurred during a time of relative peace for Christians in the Roman Empire. Sixtus I is credited with establishing certain liturgical practices and church governance structures. He is often associated with the early development of the Roman Catholic Church and is venerated as a saint, with his feast day celebrated on April 6.