Easter, also called Pascha (Greek, Latin) or Resurrection Sunday,  is a festival and holiday  celebrating the  resurrection of Jesus  from the dead, described in the New Testament as having occurred on the third day of his burial after his crucifixion by the Romans at Calvary c. 30 AD.  It is the culmination of the Passion of Jesus, preceded by Lent (or Great Lent), a forty-day period of fasting, prayer, and  penance.

Most Christians refer to the week before Easter as “Holy Week“—it contains the days of the Easter Triduum, including  Maundy Thursday, commemorating the Maundy and  Last Supper, as well as  Good Friday, commemorating the crucifixion and death of Jesus. In Western Christianity,  Eastertide, or the Easter Season, begins on Easter Sunday and lasts seven weeks, ending with the coming of the fiftieth day,  Pentecost Sunday. In Eastern Christianity, the season of Pascha begins on Pascha and ends with the coming of the fortieth day, the Feast of the Ascension.

Easter and the holidays that are related to it are moveable feasts which do not fall on a fixed date in the Gregorian or Julian calendars which follow only the cycle of the sun; rather, its date is determined on a lunisolar calendar similar to the Hebrew calendar. The First Council of Nicaea (325) established two rules, independence of the Jewish calendar and worldwide uniformity, which were the only rules for Easter explicitly laid down by the council. No details for the computation were specified; these were worked out in practice, a process that took centuries and generated a number of controversies. It has come to be the first Sunday after the ecclesiastical full moon that occurs on or soonest after 21 March, but calculations vary.

Easter customs  vary across the Christian world, and include sunrise services, exclaiming the Paschal greeting, clipping the church,  and decorating  Easter eggs  (symbols of the empty tomb).  The Easter lily, a symbol of the resurrection, traditionally decorates the chancel area of churches on this day and for the rest of Eastertide. Additional customs that have become associated with Easter and are observed by both Christians and some non-Christians include egg hunting, the Easter Bunny, and Easter parades.  There are also various traditional Easter foods that vary regionally.

Christmas or Christmas Day (Old English: Crīstesmæsse, meaning “Christ‘s Mass“) is an annual festival commemorating the birth of Jesus Christ, observed most commonly on December 25 as a religious and cultural celebration among billions of people around the world. A feast central to the  Christian liturgical year, it is prepared for by the season of Advent or the Nativity Fast and initiates the season of Christmastide, which historically in the West lasts twelve days and culminates on Twelfth Night; in some traditions, Christmastide includes an Octave. Christmas Day is a public holiday in many of the world’s nations, is celebrated culturally by a large number of non-Christian people, and is an integral part of the holiday season.

Inndependence Day of the United States, also referred to as Fourth of July or July Fourth in the U.S., is a federal holiday commemorating the adoption of the Declaration of Independence on July 4, 1776, by the Continental Congress declaring that the thirteen American colonies regarded themselves as 13 independent states, and no longer part of the British Empire. 

Independence Day is commonly associated with fireworks parades,  barbecues,  carnivals,  fairs,  picnics,  concerts,  baseball games,  family reunions, and political speeches and ceremonies, in addition to various other public and private events celebrating the history, government, and traditions of the United States.

Independence Day is the National Day of the United States.

Background

During the American Revolution, the legal separation of the Thirteen Colonies from Great Britain occurred on July 2, 1776, when the Second Continental Congress  voted to approve a resolution of independence that had been proposed in June by Richard Henry Lee of Virginia declaring the American Colonies independent from British rule. After voting for independence, Congress turned its attention to the Declaration of Independence, a statement explaining this decision, which had been prepared by a Committee of Five, with Thomas Jefferson as its principal author. Congress debated and revised the wording of the Declaration, finally approving it on July 4. A day earlier, John Adams had written to his wife Abigail:

The second day of July, 1776, will be the most memorable epoch in the history of America. I am apt to believe that it will be celebrated by succeeding generations as the great anniversary festival. It ought to be commemorated as the day of deliverance, by solemn acts of devotion to God Almighty. It ought to be solemnized with pomp and parade, with shows, games, sports, guns, bells, bonfires, and illuminations, from one end of this continent to the other, from this time forward forever more.

Adams’s prediction was off by two days. From the outset, Americans celebrated independence on July 4, the date shown on the much-publicized Declaration of Independence, rather than on July 2, the date the resolution of independence was approved in a closed session of Congress.

Historians have long disputed whether Congress actually signed the Declaration of Independence on July 4, even though Thomas Jefferson, John Adams, and Benjamin Franklin all later wrote that they had signed it on that day. Most historians have concluded that the Declaration was signed nearly a month after its adoption, on August 2, 1776, and not on July 4 as is commonly believed.

Coincidentally, both John Adams and Thomas Jefferson, the only signers of the Declaration of Independence later to serve as Presidents of the United States, died on the same day: July 4, 1826, which was the 50th anniversary of the Declaration. Although not a signer of the Declaration of Independence, but another Founding Father who became a President,  James Monroe, died on July 4, 1831, thus becoming the third President in a row who died on the holiday. Calvin Coolidge, the 30th President, was born on July 4, 1872, and, so far, is the only U.S. President to have been born on Independence Day.