William Clark (August 1, 1770 – September 1, 1838) was an American explorer, soldier, Indian agent, and territorial governor.

[7] The Clarks were planters in Virginia, owned several modest estates, and claimed ownership of several enslaved African Americans.

[9] Clark's five older brothers fought in Virginia units during the American Revolutionary War (1775–1783), but William was too young.

[7] His oldest brother, Jonathan Clark, served as a colonel during the war, rising to the rank of brigadier general in the Virginia militia years afterward.

His second-oldest brother, George Rogers Clark, rose to the rank of general, spending most of the war in Kentucky fighting against British-allied American Indians.

[citation needed] William, his parents, his three sisters, and the Clark family's slaves arrived in Kentucky in March 1785, having first traveled overland to Redstone Landing in present-day Brownsville, Pennsylvania.

In Kentucky, his older brother George Rogers Clark taught William wilderness survival skills.

In error, the undisciplined Kentucky militia attacked a peaceful Shawnee hunting camp, where they killed a total of eight men, women, and children.

[12] In 1790, Clark was commissioned by General Arthur St. Clair, governor of the Northwest Territory, as a captain in the Clarksville, Indiana militia.

[14] In 1791, Clark served as an ensign and acting lieutenant with expeditions under generals Charles Scott and James Wilkinson.

[13] At the Battle of Fallen Timbers in 1794, Clark commanded a company of riflemen who drove back the enemy on the left flank, killing a number of Native Americans and Canadians.

In 1803, Meriwether Lewis recruited Clark, then age 33, to share command of the newly formed Corps of Discovery, whose mission was to explore the territory of the Louisiana Purchase, establish trade with Native Americans, and consolidate the sovereignty of the US.

The indigenous nations treated York with respect, and many of the Native Americans were interested in his appearance, which "played a key role in diplomatic relations".

[18][19] Although Clark was refused a promotion to the rank of captain when Jefferson asked the Senate to appoint him, at Lewis' insistence, he exercised equal authority, and continued the mission.

[20] In 1807, President Jefferson appointed Clark as the brigadier general of the militia in the Louisiana Territory, and the US agent for Indian affairs.

Jefferson appointed Meriwether Lewis territorial governor of Upper Louisiana, commander-in-chief of the militia, and superintendent of Indian Affairs.

Although Clark had primary duties in dealing with the Native Americans, "the territorial governor held the title of ex officio superintendent of Indian affairs.

[23] Clark's experiences during his cross-continent expedition gave him the tools to be the ideal candidate for a diplomat to the Native Americans.

President James Madison appointed Clark as Missouri territorial governor and thus ex officio superintendent of Indian affairs in that region, during the summers of 1808 and 1813.

In Louisiana and Missouri, Clark served the United States government for the longest term in history as diplomat to the Native American peoples.

But he was aware of the consequences and he demonstrated genuine concern for the plight of destitute native people increasingly threatened with extinction, so much so that Indian-hating frontier settlers called him an "Indian lover".

[citation needed] In 1822, Clark was appointed Superintendent of Indian Affairs by President James Monroe, a new position created by Congress after the factory system was abolished.

[28] As the Superintendent of Indian Affairs, Clark was the most important man on Native American matters west of the Mississippi.

As superintendent at St. Louis, Clark took on some additional duties: he issued licenses and granted passports to traders and travelers; provided payments for injuries and injustices to both whites and Indians; invoked military force to arrest lawbreakers; prevented or terminated hostilities between tribes; removed unauthorized persons from Indian country or confiscated their property; established, marked, and surveyed boundaries; distributed annuities and made sure that treaty provisions were delivered; and conducted treaty councils.

Clark issued "an extermination order", which he gave to Lewis Cass, a man who played a central role in Jackson's removal policy.

However, in the end, relocation of the Indians from their native lands became the government's primary goal, and even the assimilated Five Civilized Tribes were moved by force (threat of military action).

Members of the Shoshone, Osage, and Mandan tribes spoke at the ceremony, marking Clark's service to these Indian nations during the final years of his life.