DUBLIN, IRELAND Half a million people will parade in Dublin today to celebrate St. Patrick's Day, but since when did Irish people celebrate this holiday?

March 17 has always meant a lot to the Irish diaspora, particularly those who themselves had left the country seeking a better life abroad. It was a day to celebrate Irishness, to reminisce about home, and to stand together in solidarity. Public gatherings, and particularly parades, have always been part of the annual celebration of Irishness.

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