<Tr> <Th> Rank </Th> <Td> sergeant (honorary posthumous - Presidential citation) </Td> </Tr> <Tr> <Th> Unit </Th> <Td> Corps of Discovery </Td> </Tr> <P> York (1770--before 1832) was an African - American explorer best known for his participation with the Lewis and Clark Expedition . Enslaved by William Clark's father and passed down through a will to William Clark, he performed hard manual labor without pay, but participated as a full member of the expedition . Like many other expedition members, his ultimate fate is unclear . There is evidence that after the expedition's return, Clark had difficulty compelling York to resume his former status, and York may have later escaped or been freed, but nothing is entirely clear on this . </P> <P> York was born in Caroline County near Ladysmith, Virginia . He, his father, his mother (Rose) and younger sister and brother (Nancy and Juba), were enslaved by the Clark family . York was William Clark's slave from boyhood, and was left to William in his father's will . He had a fiance whom he rarely saw, and likely lost contact with her after 1811 when she was sold / sent to Mississippi . It is not known if York fathered any children . </P>

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