When Pope Gregory XIII corrected the calendar in 1582, he corrected it back to A.D. 325 rather than back to 46 B.C., but that was initially accepted only in the Catholic countries. The problem with the Julian calendar is that the length of the year is not exactly 365.25 days--every 128 years the calendar is one day off, and after 12 centuries the days had started to add up. Some years the date of Easter is the same by both calendars--next year is an example.
The doctrinal differences between the Eastern and Western churches were so small that they probably could have been resolved if it weren't for cultural differences and some of the personalities involved. Even after the split in 1054, the pope still responded to the emperor's appeal for help against the Turks (which turned into the First Crusade). Of course the sack of Constantinople in 1204 (Fourth Crusade) aggravated things greatly but there was already a lot of animosity before that--I have read an account of the Second Crusade written by a Frankish knight which makes that clear.
It's hard to erase 950+ years of history but maybe with good will on both sides progress can be made.
Nice summary. I don’t see any reason for this. The Jews calculate Passover based on the old or new Julian calendar?
It doesn’t really make a difference exactly what day it’s on. I mean we celebrate Xmas the same time.
Toss a coin and go with that.