The term Octave of Easter may refer either to the eight-day period (Octave) in Eastertide that starts on Easter Sunday and runs until the Sunday following Easter, inclusive; or it may refer only to that Sunday after Easter, the Octave Day of Easter (often known as Low Sunday, particularly in the Anglican Communion). That Sunday is also known historically as St. Thomas Sunday (especially among Eastern Christians), Quasimodo Sunday and Quasimodogeniti. Since 1970 Low Sunday has been officially known as the Second Sunday of Easter (referring to the Easter season) in the Roman Catholic Church. On 30 April 2000, it was also designated as Divine Mercy Sunday by Pope John Paul II.