Why is Easter so late this year, and how is the date decided?

Eggs decorate a tree in Germany

The customs that surround Easter, the reason it is a moveable feast and why it sometimes varies in Eastern and Western churches

LAST UPDATED AT 14:35 ON Fri 11 Apr 2014

IN MOST of the Christian world, Easter Sunday falls at some point between 22 March and 25 April – and this year it comes right at the end of that window. Why is it so late?

To anyone unfamiliar with the movement of the moon, the vagaries of the Julian and the Gregorian calendars, and the March equinox, the date can seem somewhat random. But in fact it's governed by strict rules:

How is Easter celebrated?
The festival of Easter, which commemorates the crucifixion and the resurrection of Christ, is celebrated differently around the world. Americans give one another painted eggs and baskets of sweets. British children go on hunts for chocolate eggs left by the Easter Bunny, while Greeks eat a traditional baked bread called tsoureki with red-dyed eggs. Many Central and Eastern Europeans also paint eggs decoratively and or fight with them like conkers and, in the Czech Republic, boys pour water on girls and symbolically whip them with willow twigs.

Why is the date of Easter not fixed?
The short answer is that early Christians wanted to observe Easter annually in correlation with the Jewish festival of Passover – and specifically, they wanted Easter to fall just after the Jewish commemoration of the flight from Egypt. This is because the Last Supper is thought to have taken place on Passover. The Hebrew calendar is based on both solar and lunar cycles, and therefore Passover a moveable feast. That in turn makes Easter a moveable feast.

Then there is another layer of complexity: Western Christians (including Protestants and Roman Catholics) and Eastern Christians (Orthodox Christians) often celebrate Easter on different dates thanks to differences in their calendars. This year, Easter will fall on the same day for both – 20 April – but next year Western Christians will celebrate Easter on 5 April and Eastern Christians on 12 April.

So how is the date calculated?
In the very early days of Christianity the First Council of Nicaea, a gathering of bishops, determined that Easter would always fall on the first Sunday after the first full moon – known as the Paschal Full Moon – following the March equinox. However, Eastern and Western churches use different calendars – Gregorian in the West and Julian in the East – and so end up with different dates · 

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