Greene was born in Apponaug, Rhode Island, one of nine children of Caleb and Sarah Robinson (Greene) Greene. His family had roots in the founding of Rhode Island and in the American Revolutionary War, including General Nathanael Greene, George's second cousin. Caleb was a financially shrewd ship owner and merchant, but the Embargo Act of 1807, which prohibited U.S. vessels from carrying goods to other countries, and the War of 1812 left his family in financial difficulties. Young George attended Wrentham Academy and then a Latin grammar school in Providence and hoped to attend Brown University there, but his impoverished father could not afford it, so he moved to New York City and found work in a dry goods store on Pearl Street.