Du Pont was born at Goodstay, his family home at
Bergen Point (now
Bayonne),
New Jersey, the fourth child and second son of
Victor Marie du Pont and Gabrielle Joséphine de la Fite de Pelleport. His uncle was
Eleuthère Irénée du Pont, the founder of
E.I. du Pont de Nemours Company, which began as a gunpowder factory and today is a multinational chemical corporation. (Samuel was the only member of his generation to use a capital
D.) Du Pont spent his childhood at his father's home,
Louviers, across the
Brandywine Creek from his uncle's estate and gunpowder factory, Eleutherian Mills, just north of
Wilmington, Delaware. He was enrolled at Mount Airy Academy in
Germantown, Pennsylvania, at age 9. However, his father was unable to fund his education because of his failing wool mill, and he was encouraged to instead enlist in the
U.S. Navy. His family's close connections with President
Thomas Jefferson helped secure him an appointment as a
midshipman by President
James Madison at the age of 12, and he first set sail aboard the 74-gun
ship of the line out of
Delaware in December 1815. As there was no naval academy at the time, Du Pont learned
mathematics and
navigation at sea and became an accomplished navigator by the time he took his next assignment aboard the
frigate in 1821. He then served aboard the
frigate in the
West Indies and off the coast of
Brazil. Though still not yet a commissioned officer, he was promoted to
sailing master during his service aboard the 74-gun in 1825, which sailed on a mission to display American influence and power in the
Mediterranean. Soon after his promotion to Lieutenant in 1826, he was ordered aboard the 12-gun
schooner , returned home for two years after his father's death in 1827, and then served aboard the 16-gun sloop in 1829. Despite the short period in which he had been an officer by this time, Du Pont had begun to openly criticize many of his senior officers, who he believed were incompetent and had only received their commands through political influence. After returning from the
Ontario in June 1833, Du Pont married Sophie Madeleine du Pont (1810–88), his first cousin as the daughter of his uncle, Eleuthère Irénée du Pont. As he never kept an officer's journal, his voluminous correspondence with Sophie serves as the main documentation of his operations and observations throughout the rest of his naval career. From 1835 until 1838, he was the
executive officer of the frigate and the sloop , commanding both the latter and the schooner in the
Gulf of Mexico. In 1838 he joined the ship in the Mediterranean until 1841. The following year he was promoted to
commander and set sail for China aboard the
brig , but was forced to return home and give up his command because of severe illness. He returned to service in 1845 as commander of the , the flagship of Commodore
Robert Stockton, reaching California by way of a cruise of the
Hawaiian Islands by the time the
Mexican–American War had begun. ==Mexican–American War==