# Marcion excommunicated in Rome (144)

URL: https://christianity-history.com/timeline/144-marcion-excommunicated-in-rome
Location: Rome
Themes: Theology

Marcion, who rejected the Old Testament and created his own canon, is expelled by the Roman church, spurring the formation of a Christian canon. At this point in the timeline (144), the Bishop of Rome was Pope Pius I (c. 140 – c. 155). Dates for the earliest bishops of Rome are traditional and uncertain.

## Why it matters
Marcion excommunicated in Rome mattered because it shaped how Christians understand God, Christ, salvation and the church.

Pope at the time: [Pope Pius I](https://christianity-history.com/popes/pope-pius-i)

## Sources
- [Wikipedia — Marcion of Sinope](https://en.wikipedia.org/wiki/Marcion_of_Sinope)
- [Encyclopaedia Britannica topic lookup — Marcion excommunicated in Rome](https://www.britannica.com/search?query=Marcion+excommunicated+in+Rome)
- [Wikipedia — Early Church (period overview)](https://en.wikipedia.org/wiki/Ante-Nicene_period)