Really, St. Nick was born around 245CE near Patara, Turkey, an important Byzantine port. When his father died, leaving him a great fortune, Nicholas, bishop of Myra (a name derived from the resin myrrh) began giving away money to the needy, especially children.
In one circumstance, a nobleman with three daughters had fallen on hard times. Things were different then, and because their father wouldn't be able to pay their dowries, they faced a life of prostitution. Hearing of their plight, St. Nicholas threw a bag of gold adequate for one daughter's marriage through a window of their shabby castle. The next night he did the same for the second daughter. The third night he found the window closed (no wonder they were having financial problems!). Ever resourceful, St Nick dropped a third bag down the chimney. Towns folk heard of the daughters good fortune, and began hanging stockings by the fireplace.
The Dutch are credited with transforming the saint into the character we know today. Their custom of giving gifts to children on the Day of Saint Nicholas was brought to America by settlers of New Amsterdam (renamed New York when the British took over the colony.)