List of U.S. (wiki says American saints, but that is not accurate.)
http://en.wikipedia.org/wiki/List_of_American_saints_and_beatified_peopleThe first U.S. Native American saint (Algonquin Mohawk), as well as one of two of the newest U.S. saints, Kateri Tekakwitha (the other Native American saints being Mexican) She died in 1680 at age 24, a few years after her conversion.
After converting, apparently, mortification of the flesh with her friend, Marie Therese became her/their favorite activity. Self flagellation, fasting, etc. She died in the arms of Marie, saying "I love you, Jesus." One of the miracles that supposedly occurred after her death--she turned white and beautiful (in the eyes of her beholders, of course).
http://en.wikipedia.org/wiki/Kateri_TekakwithaThe other U.S. saint beatified in 2012 is St,. Marianne Cope, who founded a hospital for lepers in Hawaii in response to a plea for help from Hawaii's King Kalākaua. Among those treated was leper and fellow U.S. saint, Father Damien. She never caught the disease, which was considered a miracle.
http://en.wikipedia.org/wiki/Marianne_Cope