Why are St. Patrick's Day celebrations held in countries around the world?

Answer 1

Because Irish people have travelled all around the world and they and their descendants continue to celebrate St. Patrick's Day. As Ireland and its people are quite welcome wherever they go, locals in those countries have also joined in and helped to organise St. Patrick's Day celebrations.

Answer 2

St. Patrick is the patron saint of Ireland. He is credited with bringing Christianity to Ireland. The 17th of March is his feast day. It is also Ireland's national holiday. There are celebrations all over Ireland on that day. As many Irish people emigrated to other countries, they and their descendants are now found in many countries. Many people claim Irish ancestry, even if they are not from Ireland themselves. With so many Irish people and people of Irish descent in countries around the world, the practice of celebrating St. Patrick has now become common in many countries. So in places where there are a particularly large Irish community, there will be St. Patrick's Day celebrations.