Henry, Andrew, fur trader (c. 1775-Jan. 10, 1832). Born in Fayette County, Pennsylvania, he was well educated but wrote almost nothing that has survived. In 1806 he became a partner in a Missouri lead mine. Henry joined Lisa and others in forming the St. Louis Missouri Fur Company and in 1809 became field captain, leading an expedition to the Three Forks, in the Montana mountains, where in April 1810, he commenced building a fort. Blackfeet difficulties prevented very successful fur gathering and in 1811 Henry and his party appeared among the Mandans after exploring the Montana-Idaho wilderness, discovering Lake Henry, building a post near present St. Anthony, Idaho, and splitting his party into three important segments, each with a role in exploration of the northwest. Henry returned to St. Louis, enrolled in the War of 1812, becoming a Major. In 1822 he became associated with Ashley in a renewal of the northwestern fur hunt and left in April for the upper Missouri. Henry intended to winter at the mouth of the Yellowstone River, but pushed on up to near the mouth of the Musselshell River. In exploring toward Three Forks, he lost four men to Blackfeet and withdrew in April 1823, to the mouth of the Yellowstone River. Learning of Ashley's fight with the Arikaras, Henry pushed downstream by boat, joined Ashley for the inconclusive Leavenworth campaign against the Arikaras, and Henry and a party of trappers then began the overland return to the Yellowstone. They were attacked by Mandans but continued, Henry wintered in 1823-1824 at his Yellowstone post, and in the fall of 1824 bringing a good fur catch to St. Louis. He retired to his home in Washington County, Missouri, where he died.