Simplify the following text for a Grade 6 native English-speaking person.
Original: The schism arose in the Church of the East in 1964 in resistance to these changes made to the church , thereby causing two separate Church of the East branches to be created including the Ancient Church of the East headquartered in Baghdad and the Assyrian Church of the East headquartered in Chicago .
Simplified: The Ancient Church of the East separated from the Assyrian Church of the East .