Christian

This is the day when Western Christians celebrate the birth of Jesus Christ. It marks the end of Advent and the beginning of the 12 days of Christmas. Wikipedia

Epiphany is a day in the Christian calendar celebrating the Magi from the east visiting the infant Jesus. Eastern Christianity celebrates this event about two weeks later.) (Wikipedia)

Ash Wednesday is a holy day of prayer and fasting in many Western Christian denominations. It is preceded by Shrove Tuesday and marks the first day of Lent, the six weeks of penitence before Easter. (Wikipedia)

The day commemorates Saint Patrick and the arrival of Christianity in Ireland, and, by extension, celebrates the heritage and culture of the Irish in general. Celebrations generally involve public parades and festivals, and the wearing of green attire or shamrocks. (Wikipedia)

Mothering Sunday is a day honouring mother churches, the church where one is baptized and becomes "a child of the church". It is celebrated in the UK, Ireland, and some Commonwealth countries. (Wikipedia)

Palm Sunday happens on the Sunday before Easter. The day commemorates Christ's triumphal entry into Jerusalem. Its name originates from the palm branches waved by the crowd to greet and honor Jesus as he entered the city. (Wikipedia)

Good Friday is a Christian holiday commemorating the crucifixion of Jesus and his death at Calvary. For many it is a day of fasting and religious services. (Wikipedia)

Easter Sunday is a Christian festival commemorating the resurrection of Jesus from the dead. It brings an end to Holy Week which began with Palm Sunday. The western and eastern churches celebrate Easter on different days. (Wikipedia)

Pentecost is the Christian holiday that happens 50 days after Easter. It commemorates the descent of the Holy Spirit upon Mary, mother of Jesus and the Apostles of Jesus while they were in Jerusalem. Wikipedia 

Lammas, or Loaf Mass is a Christian holiday celebrated in some northern countries. Like Lughnasadh, the Celtic holiday which falls on the same day, Lammas is a celebration of the first fruits of the new harvest. (Wikipedia)