Key Terms : Trans-Atlantic Prologue Atlantic World- TheAtlantic Worldis the history of the interactions among the peoples and empires bordering theAtlanticOcean rim from the beginning of the Age of Discovery to the early 21st centuryChristendom- the worldwide body or society of Christians.Great Schism- Thisschismhappened gradually over centuries and became official in the year1054. It had political and religiouscauses. The politicalcausewas the splittingof the Roman Empire. In the 400s AD, the Roman Empire split into a western empire (capital at Rome) and an eastern empire (capital at Constantinople).Charlemagne's crowning made the Byzantine Emperor redundant, and relationsbetweenthe East and the West deteriorated until a formalsplitoccurred in 1054. The EasternChurchbecame the GreekOrthodox Churchby severing all ties withRomeand theRoman Catholic Church— from the pope to the HolyRomanEmperor on down.