The amount of indentured servitude dropped dramatically throughout the country. An Act Prohibiting Importation of Slaves sailed through Congress with little opposition. President Thomas Jefferson supported it, and it went into effect on January 1, 1808.
On January 8, 1808, Fulton married Harriet Livingston (1786–1824), the daughter of Walter Livingston and niece of Robert Livingston, prominent men in the Hudson River area, whose family dated to the colonial era. Harriet, who was nineteen years his junior, was well educated and was an accomplished amateur painter and musician. Together, they had four children.