Editing Pope Pius I (section)

==Pontificate==
According to [[Catholic tradition]], Pius I governed the church in the middle of the 2nd century during the reigns of the Emperors [[Antoninus Pius]] and [[Marcus Aurelius]].<ref name=lives/> He is held to be the ninth successor of [[Saint Peter]],<ref name="newadvent.org"/> and to have decreed that [[Easter]] should only be kept on a Sunday. Although he is said to have ordered the publication of the ''Liber Pontificalis'',<ref name="lives"/> in fact compilation of that document was not started before the beginning of the 6th century.<ref>{{cite book |title=Dictionnaire historique de la papauté |first=Philippe |last=Levillain |publisher=Fayard |date=1994 |pages=1042–1043}}</ref> Pius is also said to have built one of the oldest churches in Rome, [[Santa Pudenziana]].

[[Justin Martyr]] taught [[Catechism|Christian doctrine]] in Rome during the pontificate of Pius I but the account of Justin's  martyrdom does not name Pius. Given the brevity of the account this is hardly remarkable.<ref>{{cite web |url=https://www.newadvent.org/fathers/0133.htm |title=The Martyrdom of Justin |website=New Advent}}</ref> The [[heresy|heretics]] [[Valentinus (Gnostic)|Valentinus]], [[Cerdo (gnostic)|Cerdo]]n, and [[Marcion of Sinope|Marcion]] visited Rome in Pius' time, and he is believed to have [[Excommunication|excommunicated]] both groups.<ref>{{cite book |last1=Delaney |first1=John J. |title=Dictionary of Saints |date=2005 |publisher=Image/Doubleday |location=New York |isbn=0-385-51520-0 |edition=2nd}}</ref>
Catholic apologists see this as an argument for the primacy of the [[Holy See|Roman See]] during the 2nd century.<ref name="lives"/> 

There is some conjecture that Pius was a [[Christian martyrs|martyr]] in Rome, a conjecture that entered earlier editions of the ''[[Roman Breviary]]''. The study that had produced the [[Mysterii Paschalis|1969 revision]] of the [[General Roman Calendar]] stated that there were no grounds for his being considered a martyr,<ref>{{cite book |title=Calendarium Romanum |publisher=Libreria Editrice Vaticana |date=1969 |page=129}}</ref> and he is not presented as such in the current ''[[Roman Martyrology]]''.<ref>{{cite book |title=Martyrologium Romanum |publisher=Typis Vaticanis |date=2004 |isbn=88-209-7210-7}}</ref>