Peter was born of a distinguished family in Catalonia, Spain in 1581. He joined the Society of Jesus (Jesuits), and after his novitiate in Taragona was sent to the college of Montesione, at Palma in Majorca. There he met Brother Alphonse Rodriguez (also a saint), the humble porter of the convent. Alphonse set Peter's soul on fire to save the souls of the African slaves — thousands being lost because there was no one to minister to them. His superiors finally sent Peter to New Granada in April of 1610. He was never to return to his native Spain.

By 1615 Peter finished his studies and was ordained a priest in Cartagena. When he made his final vows, he added a personal one: Peter, slave of the slaves for ever. Here in this busy seaport city, in a hot, humid, tropical climate, Father Claver spent most of his priestly life. Cartegena was the principal slave market for the New World. Thousands of blacks were brought there, herded into warehouses and auctioned to the highest bidder. Captured in Africa, these slaves were chained in groups of six and crammed into the lower holds of ships designed to hold 100-200, but holding 600-800 humans. Their treatment was so inhumane that 1/3 of the slaves died in the sea journey.

It was to these people that Peter would minister. He would meet each slave ship as it arrived. Peter would go to the warehouses and bring them food, water, medicine and clothing, for, as he said "We must speak to them with our hands, before we try to speak to them with our lips". But most of all, he brought them God. While nursing them back to health, he would teach them of Christ, explain to them that they were loved by God more than they were abused by man, and that evil outraged God. He offered their only consolation: hope in the promises of God. Nearly three hundred thousand of them received baptism at his hands.

After twenty-seven years of devotion to the black slaves, St. Peter Claver died at Cartagena on September 8, 1654. Leo XIII canonized him on January 15, 1888, proclaiming him special patron and protector of the negroes. St. Alphonsus Rodriguez, porter of the college, who inspired Peter to become a missionary for the slaves was canonized at the same time.

http://www.catholicculture.org/culture/liturgicalyear/calendar/day.cfm?date=2014-09-09