Easter arrived early this year. Only rarely does the festival come on its earliest possible date, March 22. (It last did so in 1818 and will not do so again until 2285.) But not uncommonly Easter comes toward the end of March; it was March 26 this year as it was in 1978 and 1967. It fell on March 25 in 1951.
Pfatteicher, Phillip H., "The Moon and the Mystery: Expanding Our Horizons" (1989). Institute of Liturgical Studies Occasional Papers. Paper 48.