Overview

Easter changes date every year because it is a religious holiday, based on the lunar calendar, and the lunar calendar doesn't align with the Gregorian calendar commonly used in most of the world.  Easter is celebrated on the first Sunday after the first full moon that occurs after the spring equinox.


Explanation

The New Testament says that Jesus's resurrection occurred around Passover, which was celebrated on the first full moon after the spring equinox.

In 325 AD, the Council of Nicaea decided that Easter should be celebrated on the first Sunday after the first full moon after the spring equinox.  The lunar month is always 29.5 days long, but the Gregorian calendar months are are varying lengths, therefore they can never sync.  Thus, as the date of the full moon changes, so Easter's date changes as well.

The date of Easter Sunday is commonly defined as the first Sunday that falls after the full moon (sometimes called the Easter or Paschal Full Moon), that occurs after the spring equinox.  As the precise computation of the movements of the spring equinox and the astronomical full moon is complex and laborious the determination of Easter Sunday has always been based on a simplified method.

For purposes of this simplified method, the date of the spring equinox is fixed as 21 March. The Easter Full Moon is the tabular full moon that occurs on or after 21 March and the first Sunday that occurs afterwards is Easter Sunday  The earliest possible date for Easter Sunday is thus 22 March, which can only occur when the Easter Full Moon falls on Saturday 21 March. Easter can then fall on any Sunday between March 22 and April 25.

The following tables list the date of Easter Sunday for the years 1600 through 2099, as calculated by the U. S. Government's Census Bureau.  Nice to have available, but why the heck would they bother to do that?  Who knows.  Your (our?) government does many mysterious things, for no apparent reason.  Except, maybe, to justify spending more tax dollars.

Easter Dates: 1600 - 1699.

Easter Dates: 1700 - 1799.

Easter Dates: 1800 - 1899.

Easter Dates: 1900 - 1999.

Easter Dates: 2000 - 2099.