Zero, seven, twenty-eight, thirty-five

I · Thirteen days that never existed

The state moved its calendar and the Easter reckoning stayed behind

Romania entered 1919 with two calendars on the same territory: Transylvania and Bukovina were on the new style, while the Old Kingdom and Bessarabia had stayed on the old one. In March the government passed decree-law 1053: the day that would have been 1 April 1919 was to be called 14 April instead. In the part of the country still keeping the old style, the days between 1 and 13 April did not exist that year. Five years later, in October 1924, the Romanian Orthodox Church took the same step for its fixed feasts, and 1 October was called 14 October.

One thing was left untouched: the reckoning that finds the date of Easter. It comes from Alexandria, it works on the old calendar, and there it stayed, together with everything that hangs on it. Hence an asymmetry that anyone with relatives in both confessions can see: a Romanian Orthodox and a Romanian Catholic arrive at Christmas together every year, and at Easter only now and then. In this century, in 31 years out of 100.

II · Why only four

Two full moons that stand either side by side or a month apart

Both feasts fall on a Sunday: each is the first Sunday after the paschal full moon of its own calendar. That gives the first half of the answer, since the difference between two Sundays is always a multiple of seven days.

The second half is in the moons. The two calendars do not look at the same full moon: each has its own table of spring full moons, and the old table has fallen behind. In this century the old calendar's full moon comes four or five days after the new calendar's in 73 years out of 100. In the other 27, the old table skips the full moon the other one uses and takes the next, and the offset rises to 34 or 35 days.

Nothing settles between those two situations. From 1583 to 2436, the two full moons are either at most seven days apart or at least 33 days apart. Because each full moon is carried forward to the Sunday after it, the first case yields zero days or seven, and the second yields 28 or 35. A gap of two or three weeks would require the full moons to stand between eight and 32 days apart, and the tables put nothing there.

III · 1926 and 1929

Romania's two attempts landed squarely on the wide gaps

The Romanian Orthodox Church reckoned Easter by the new rule twice, in 1926 and in 1929, then returned to the old one and stayed there. Both attempts fell in years when the split was visible to the naked eye.

In 1926 the two dates stood 28 days apart, the rarest of the four distances: the official feast fell on 4 April while the old reckoning put it on 2 May. In 1929 it was 35 days, the widest gap there can be, with 31 March on one side and 5 May on the other. A country kept Easter twice that year, five weeks apart.

Of those 854 years, only 27 bring a four-week separation. One of them is 1926.

The disagreement left behind communities that keep the uncorrected calendar to this day, with their own churches and their feasts moved thirteen days. For everyone else, the return to the old reckoning means that Romanian Orthodox Easter is still calculated on a calendar the country uses for nothing else.

IV · What moves with Easter

Five statutory holidays hang on the same reckoning

Good Friday, the two days of Easter and the two days of Pentecost are public holidays on which work stops in Romania, and all five move each year with the date of the Resurrection. The law goes further and grants those days to employees of other Christian denominations on the dates their own churches keep, which means that in some years a single Romanian company has two Easter breaks five weeks apart.

The room for movement is tightly bounded. Between 1919 and 2100, Orthodox Easter never falls earlier than 4 April or later than 8 May, and in 33 years out of 182 it lands in May. Western Easter, reckoned on the other table, can come as early as 23 March.

V · The bar wears out

In 2698 the two feasts share a day for the last time

The old calendar falls behind by three days every 400 years, and the offset grows quietly. The first distance to go is four weeks: after 2092 it never appears again. In 2437 a new rail opens at six weeks, one that had stood empty until then. In 2725 a two-week separation appears for the first time — precisely the one missing from all the history before it.

And the years with a single Easter thin out until they stop altogether. The last is 2698. After that, the two feasts never fall on the same day again.

VI · How the dates were reckoned

Two rules, applied year by year

The dates on this page come from the two official reckonings. The first is the Gregorian computus, used by the Catholic Church since the 1582 reform. The second is the Alexandrian paschalion on the Julian calendar, used by the Orthodox churches, the Romanian one among them. The Orthodox dates are carried over into today's calendar so that they can stand beside the others and be compared in days.

The simplest check holds every time: all 2,636 dates obtained for the years from 1583 to 2900 fall on a Sunday, and the years tested match the published tables. A recent example anyone can verify: 2025, when both fell on 20 April, and 2024, when they were 31 March and 5 May.

Every figure above holds as long as the two rules stay as they are. These are calendars made by people, and those people have changed them once already and can change them again.