Thomas was born at Newsom's Depot, Southampton County, Virginia, five miles (8 km) from the North Carolina border. His father, John Thomas, of Welsh descent, and his mother, Elizabeth Rochelle Thomas, a descendant of French Huguenot immigrants, had six children. George had three sisters and two brothers. The family led an upper-class plantation lifestyle. By 1829, they owned and 15 slaves. John died in a farm accident when George was 13, leaving the family in financial difficulties. George Thomas, his sisters, and his widowed mother were forced to flee from their home and hide in the nearby woods during Nat Turner's 1831 slave rebellion. Benson Bobrick has suggested that while some repressive acts were enforced following the crushing of the revolt, Thomas took the lesson another way, seeing that slavery was so vile an institution that it had forced the slaves to act in violence. This was a major event in the formation of his views on slavery; that the idea of the contented slave in the care of a benevolent overlord was a sentimental myth. Christopher Einolf, in contrast wrote "For George Thomas, the view that slavery was needed as a way of controlling blacks was supported by his personal experience of Nat Turner's Rebellion. ... Thomas left no written record of his opinion on slavery, but the fact that he owned slaves during much of his life indicates that he was not opposed to it." A traditional story is that Thomas taught as many as 15 of his family's slaves to read, violating a Virginia law that prohibited this, and despite the wishes of his father.