Easter is always the 1st Sunday after the 1st full moon after the Spring
Equinox (which is March 20). This dating of Easter is based on the lunar
calendar that Hebrew people used to identify Passover, which is why it
moves around on our Roman calendar.
Based on the above, Easter can actually be one day earlier (March 22)
than it will be this year (200 
but that is pretty rare.
This year is the earliest Easter any of us will ever see the rest of our
lives! And only the most elderly of our population have ever seen it
this early previously (95 years old or above!). And none of us have ever, or will
ever, see it a day earlier! Here are the facts:
1) The next time Easter will be this early (March 23) will be the year
2228 (220 years from now). The last time it was this early was 1913 (so if
you’re 95 or older, you are the only ones that were around for that!).
2) The next time it will be a day earlier, March 22, will be in the year
2285 (277 years from now). The last time it was on March 22 was 1818.
No one alive today has or will ever see it any earlier than this year.
