Born a slave in Dorchester County, Maryland, Tubman was beaten and whipped by her various masters as a child. Early in life, she suffered a traumatic head wound when an irate slave owner threw a heavy metal weight intending to hit another slave and hit her instead. The injury caused dizziness, pain, and spells of hypersomnia, which occurred throughout her life. She was a devout Christian and experienced strange visions and vivid dreams, which she ascribed to premonitions from God.
In 1849, Tubman escaped to Philadelphia, then immediately returned to Maryland to rescue her family. Slowly, one group at a time, she brought relatives with her out of the state, and eventually guided dozens of other slaves to freedom. Traveling by night and in extreme secrecy, Tubman (or "Moses", as she was called) "never lost a passenger". Her actions made slave owners anxious and angry, and they posted rewards for her capture. When a far-reaching United States Fugitive Slave Law was passed in 1850, she helped guide fugitives further north into Canada, and helped newly freed slaves find work.
When the US Civil War began, Tubman worked for the Union Army, first as a cook and nurse, and then as an armed scout and spy. The first woman to lead an armed expedition in the war, she guided the raid at Combahee Ferry, which liberated more than seven hundred slaves. After the war, she retired to the family home on property she had purchased in 1859 in Auburn, New York, where she cared for her aging parents. She was active in the women's suffrage movement until illness overtook her and she had to be admitted to a home for elderly African-Americans that she had helped to establish years earlier. After she died in 1913, she became an icon of American courage and freedom.