Henry Harmon Spalding (born c. 1803, Bath, New York, U.S.—died c. 1874, Lapwai, Oregon Country [now in Idaho, U.S.]) was a U.S. Presbyterian missionary who, with his wife, Eliza, in 1836 established the Lapwai Mission (near present-day Lewiston, Idaho) with the first white home, church, and school in what is now Idaho.
Spalding was educated at Plattsbury (New York) Academy, Western Reserve College (Ohio), and Lane Theological Seminary (Cincinnati) and was ordained in the Presbyterian ministry in 1835. He was first appointed to the Osage Indian mission in western Missouri and then went west with the party of Marcus Whitman in 1830. In 1836 the Whitmans founded a mission among the Cayuse people at Waiilatpu, near present-day Walla Walla, Washington, while the Spaldings established a mission among the Nez Percé at Lapwai, Idaho, 125 miles (200 km) northeast of Waiilatpu. The printing press that Spalding and his wife brought in 1839 was the first in the Pacific Northwest, though he struggled to learn and document the Nez Percé language. Seeking to convert and “Westernize” the Native peoples, Spalding and Whitman helped them build permanent houses, till the fields, and irrigate crops. They also taught them how to erect mills for grinding corn and wheat, and the wives established mission schools. Known for his fiery temper, Spalding would sometimes inflict both verbal and physical abuse on those to whom he was supposedly ministering. He was an outspoken opponent of Roman Catholic missionary work in the region, which was having a larger impact.
The Lapwai mission was closed in 1847 after the Whitmans and 11 other white settlers were massacred at the Waiilatpu mission. In 1871 the Presbyterian Church resumed the work among the Nez Percé, and Spalding continued his work there until his death.