While Saint Patrick 's Day has long been the preserve of Guinness-drinking revellers painting the world 's towns green while wearing shamrock hats , Irish Catholics have always taken pride in their nation 's patron saint . Now a new study from Cambridge University based on his writings suggests Saint Patrick was not brought to Ireland as a slave , as the legend has it , but that in fact he may actually have sold slaves his family owned to pay his way to Ireland -- in order to avoid a job as a tax collector for the Roman empire . The findings fly in the face of the classic account of the life of Saint Patrick , who grew up as a member of the Roman nobility in western Britain and was supposedly abducted and forced into slavery in Ireland around 400 A.D . According to this history , Patrick escaped and became a priest before having a vision and returning to Ireland to convert the Irish to Christianity . Legend has it Saint Patrick used the shamrock , now the national emblem of Ireland , to explain the concept of the Holy Trinity , by showing an unbeliever the three-leafed plant with one stalk . The new study , based on Patrick 's own writings in their historical context , argues that Patrick actually ended up in Ireland in order to avoid becoming a `` Decurion , '' or Roman tax collector -- a role in city government that had become undesirable and dangerous in Patrick 's time . `` In the troubled era in which Patrick lived , which saw the demise and eventual collapse of Roman government in Britain in 410 , discharging the obligations of a Decurion , especially tax-collecting , would not only have been difficult but also very risky , '' said Dr. Roy Flechner , from the Department of Anglo-Saxon , Norse and Celtic at Cambridge University . Patrick 's father was a Decurion , which was a hereditary role , and when he vacated his position in order to join the clergy , Flechner says Patrick chose to leave Britain to avoid being obligated to take up his father 's job . In order to get to Ireland , which lacked a monetary system at the time , Patrick would have needed to sell commodities to finance the trip . According to his writings , Patrick 's family owned several slaves -- a high value and easily transportable commodity -- and Flechner says in the historical context it makes sense that Patrick would convert his family wealth into slaves he could sell in order to pay his way . But Philip Freeman , author of the biography `` St. Patrick of Ireland , '' says while it is almost certain that Patrick 's family owned slaves , as many members of the Roman nobility did at the time , experts ' claims that Patrick himself was a slave trader is reading too far into the sources . `` It 's almost certain that Patrick grew up surrounded by slaves , but there 's no good reason for thinking he was a slave trader , '' Freeman told CNN . `` The only sources we have about Patrick that are really reliable are the two letters he wrote when he was an old man , '' he said . `` And both of those tell the story of a young man who grew up in the young Roman nobility in Britain , but was kidnapped when he was 16 years old . '' Cambridge University 's Roy Flechner believes the widely accepted history of Saint Patrick 's early life and kidnapping was largely concocted by Patrick himself in those letters . `` The traditional story that Patrick was kidnapped from Britain , forced to work as a slave , but managed to escape and reclaim his status , is likely to be fiction : the only way out of slavery in this period was to be redeemed , and Patrick was never redeemed . The traditional legend was instigated by Patrick himself in the letters he wrote , because this is how he wanted to be remembered , '' he said . Flechner says it is only Patrick 's motives , and not his efforts to Christianize the Irish people , that are up for debate . `` None of this is to say that Patrick was not a bishop or that he did not engage in missionary activity , but his primary motives for moving to Ireland were most likely to escape the poisoned chalice of his inherited position in Roman Britain , '' he added . While very little is known about Saint Patrick , one legend has credited him with having driven the snakes out of Ireland . However , most biologists maintain there never were snakes in Ireland .
St. Patrick 's Day is the feast day St. Patrick , patron saint of Ireland . Study : Patrick may have sold slaves in order to pay his way to Ireland to avoid tax collector job in Britain . Comment: Legend : Patrick used shamrock , national emblem of Ireland , to explain concept of Holy Trinity .