St. Patrick of Ireland is one of the world's most popular saints. He was born in Roman Britain and when he was fourteen or so, he was captured by Irish pirates during a raiding party and taken to Ireland as a slave to herd and tend sheep. At the time, Ireland was a land of  Druids and pagans but Patrick turned to God and wrote his memoir, The Confession. In The Confession, he wrote:

"The love of God and his fear grew in me more and more, as did the faith, and my soul was rosed, so that, in a single day, I have said as many as a hundred prayers and in the night, nearly the same. I prayed in the woods and on the mountain, even before dawn. I felt no hurt from  the snow or ice or rain." 

Patrick's captivity lasted until he was twent, when he escaped afte  having a dream from God in which he was told to leave Ireland by goin  to the coast. There he found some sailors who took him back to Britai and was reunited with his family. 

A few years after returning home, Patrick saw a vision he described in his memoir: 

A few years after returning home Patrick saw a vision he described in his memoir:ied many letters, and he gave me one of them. I  read the heading: 'The Voice of the Irish.' As I began the letter, I  imagined at that moment that I heard the voice of those very people who  were near the wood of Foclut, which is beside the western sea-and they  cried out, as with one voice: 'We appeal to you, holy servant boy, to  come and walk among us.'"

The vision prompted his studies for the priesthood. He was ordained by St. Germanus, the Bishop of Auxerre, whom he had studied under for years, and was later ordained a bishop and sent to take the Gospel to  Ireland.

Patrick arrived in Slane, Ireland on March 25, 433. There are several legends about what happened next, with the most prominent claiming he met the chieftain of one of the druid tribes, who tried to kill him.  After an intervention from God, Patrick was able to convert the chieftain and preach the Gospel throughout Ireland. There, he converted many people -eventually thousands - and he began building churches across the country his first stone church was built in Armagh which is now called the ecclesiastical capital of Ireland

He often used shamrocks to explain the Holy Trinity and entire kingdoms were eventually converted to Christianity after hearing  Patrick's message.

Patrick preached and converted all of Ireland for 40 years. He worked many miracles and wrote of his love for God in Confessions. After years of living in poverty, travelling and enduring much suffering he died on March 17, 461. A half a century later the golden era of Irish Christianty blossomed from the foundation of St Patrick.