St Patrick's Day: Everything you need to know
- Published
WATCH: What is St Patrick's Day?
Millions of people around the world celebrate St Patrick's Day on 17 March every year.
It is a celebration of Irish history and culture, and is a national holiday in the Republic of Ireland and Northern Ireland.
St Patrick is the patron saint of Ireland.
Who was Saint Patrick?
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St Patrick is the patron saint of Ireland and is celebrated for bringing Christianity to the country.
He is thought to have grown up in Britain, during Roman times, but was kidnapped and taken to Ireland as a slave.
Once he was free again, he trained as a priest, and went back to Ireland to convert thousands of people to Christianity.
The dates of Patrick's life cannot be fixed with certainty, but sometime after 431 AD, Patrick was appointed as successor to St Palladius, the first bishop of Ireland.
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A shamrock, a symbol of St Patrick's Day and Ireland
Patrick established his headquarters at Armagh. Tradition credits him with being the first bishop of Armagh and Primate of Ireland.
He is traditionally associated with the shamrock, a type of clover and is often pictured holding one.
The three-leaved plant, symbolic of Ireland and of St Patrick's Day has an important meaning for Christians.
It is said to represent the Holy Trinity of the Father, Son and Holy Spirit. The three leaves of a shamrock are also said to stand for faith, hope and love.
A fourth leaf is said to be where we get the luck from - you may have heard of 'lucky clover'.
Did Saint Patrick drive the snakes out of Ireland?
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This is one of the famous legends around St Patrick but the chances are it didn't happen, because it's unlikely there ever were any snakes in Ireland.
The snake may be a reference to serpent, a symbol of evil, and the driving out a reference to Patrick's mission to rid Ireland of pagan - or non-Christian religious - influence.
What happens on Saint Patrick's Day?
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Crowds enjoy watching the Irish dancers in Belfast
Saint Patrick's Day started as a religious feast to celebrate the work of Saint Patrick, but it has grown to be an international festival celebrating all things Irish.
People take part in parades and dancing, eat Irish food, and enjoy huge firework displays.
The day is also famous around the world for people wearing shamrocks, dressing up as bearded Irish fairies called leprechauns, and wearing all green.
Dublin's famous St Patrick's Parade often features bands from around the world.
Parades
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Some parades have already happened, such as a big one in London on 12 March.
London's community celebrated St Patrick's Day Festival with a parade including performances by marching bands, sports clubs and Irish dancing schools.
More than 50,000 people were estimated to have joined to admire Irish dancing, food and music.
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These children went to watch the London parade
The parade in Toyko, Japan also took place last weekend.
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As did one in Mexico City.
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Here are some shots from past celebrations...
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Huge crowds gather in Dublin for the annual parade
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These people watching the show are wearing leprechaun hats
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Pipers formed part of the 2022 parade in New York, passing St Patrick's Cathedral in Manhattan
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In Sydney, Australia, these Irish dancers performed outside a restaurant
And sometimes buildings around the world are turned green for the occasion...
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The London Eye
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St Patrick's Island, Skerries, Ireland
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Nelson's Column in Trafalgar Square, London
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Empire State Building, New York, USA
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In the US city of Chicago they even dye the river green!