Easter is the most important feast in the Christian liturgical calendar, commemorating the resurrection of Jesus Christ on the third day after his crucifixion, as described in the New Testament. The events of Easter are preceded by Lent, a 40-day period of fasting and penitence beginning on Ash Wednesday, and Holy Week, which includes Palm Sunday, Maundy Thursday, and Good Friday. The resurrection narrative is central to Christian theology, and Easter has been celebrated by Christian communities since the 2nd century AD.

The English word "Easter" likely derives from Eostre (or Ostara), a Germanic goddess of spring and dawn mentioned by the 8th-century English monk Bede. However, many other languages use names derived from the Hebrew word Pesach (Passover), such as Pasqua in Italian, Pascua in Spanish, and Paques in French. This reflects the fact that the Last Supper is believed to have been a Passover Seder, and the earliest Christians celebrated Easter in conjunction with Passover.

The date of Easter is not fixed in the civil calendar. It was established at the First Council of Nicaea in 325 AD as the first Sunday following the first full moon occurring on or after the March equinox. This means Easter can fall on any Sunday between March 22 and April 25. The calculation of Easter's date, known as "computus," was one of the great intellectual challenges of the medieval period and drove significant advances in astronomy and mathematics.

The Easter egg is one of the most recognized symbols of the holiday, representing new life and resurrection. The practice of decorating eggs dates back to at least the 13th century, when eggs were forbidden during Lent and were decorated and given as gifts on Easter Sunday. In Ukraine, the art of pysanky involves writing intricate patterns on eggs using a wax-resist dyeing method, a tradition that predates Christianity and carries deep symbolic meaning in each motif and color.

The Easter Bunny tradition originated among German Lutherans in the 17th century, where a hare called "Osterhase" or "Oschter Haws" was said to judge whether children had been good or disobedient at the start of the Easter season. Good children would find colored eggs in nests they had made from caps and bonnets. German immigrants brought the tradition to America in the 1700s, where it evolved into the modern Easter egg hunt. The White House Easter Egg Roll, first hosted by President Rutherford B. Hayes in 1878, remains an annual tradition on the South Lawn.

In Greece, Easter is the most important holiday of the year, surpassing even Christmas. On Holy Saturday night, congregations gather at midnight holding unlit candles. At the stroke of midnight, the priest announces "Christos Anesti" (Christ is risen), and a single flame is passed from candle to candle until the entire church is alight. Fireworks erupt, church bells ring, and families go home to break their Lenten fast with a meal of magiritsa, a soup made from lamb offal. On Easter Sunday, whole lambs are roasted on spits, and families crack dyed red eggs against each other in a game called tsougrisma.