There are many bios of Harriet Tubman See www.nyhistory.com/harriettubman/life.htm, or go to Google. She was born ca. 1820 in MD, married a freedman, John Tubman, at age 25, escaped to Canada, and thereafter worked with the underground railroad helping slaves to freedom. During the war, she worked as a nurse and spy. After the war, she returned to NY and was active in womens rights, and ran a home for the aged. She died in 1913.
The Georgia Sea Islands extend along most of the Georgia coast; sometimes the adjacent SC coast to Port Royal is included in discussions.