Saint Patrick's day

 
Saint Patrick is the patron saint and national apostle of Ireland.
 St Patrick is credited with bringing christianity to Ireland. Saint Patrick described himself as a "most humble-minded man, pouring forth a continuous paean of thanks to his Maker for having chosen him as the instrument whereby multitudes who had worshipped idols and unclean things had become the people of God."
 
'Why is the Shamrock the National Flower of Ireland ?'               
  The reason is that St. Patrick used it to explain the Holy Trinity to the pagans. Saint Patrick is believed to have been born in the late fourth century, and is often confused with Palladius, a bishop who was sent by Pope Celestine in 431 to be the first bishop to the Irish believers in Christ.

Why Saint Patrick's Day?
Saint Patrick's Day has come to be associated with everything Irish: anything green and gold, shamrocks and luck. Most importantly, to those who celebrate its intended meaning, St. Patrick's Day is a traditional day for spiritual renewal and offering prayers for missionaries worldwide.
So, why is it celebrated on March 17th? One theory is that that is the day that St. Patrick died.

ST PATRICKS DAY PARADES WORLDWIDE 2012
USA, Canada, Ireland, UK, Australia, NZ