Conversation so far:
When was the last time Easter was on March 29
Easter Sunday last fell on March 29 in 1970.
When will be the next time Easter will fall on March 29
Next time Easter will fall on March 29 will be in the year 2043.
Why is the observance date for Easter on Sundays
The Council of Nicaea in 325 decreed that Easter should be observed on the first Sunday following the first full moon after the spring equinox which is on March 21.

Question: When was the first one ever recorded in history
Self-contained rewrite: When was the first observance of Easter Sunday ever recorded in history