Meriwether (1774-1809) and William (1770-1838) set out in May 1804 to explore and [?] the American . Lewis and Clark were accompanied by a crew of men and later, the [?] Indian guide and interpreter (also spelled ) and her newborn . They travelled by and by land from [?], Missouri, to the Oregon coast, and back again.


President Thomas commissioned Lewis to head an to explore the newly-bought Territory ( Purchase). This was the first official expedition to cross the continent to the . Lewis chose his old Clark as co-leader of the expedition.
On May 14, 1804, 45 men (known as the ) in three boats, left St. Louis, Missouri, heading west on the River. Half of the men went on the entire [?] to the Pacific and back; the other half turned back to bring maps and scientific back to the President.
Lewis and Clark were joined in North Dakota by the guide, and interpreter (1788-1812) and her newborn son, called (his nickname was Little Pomp). She traveled with the group west to the Pacific and back to North Dakota.
Lewis and Clark returned as . Their journey took 2 years, 4 months, and 10 days; they covered over 8,000 miles. Their expedition was the first to describe the grizzly bear and the .