
American
Moses Splawn was an American prospector who, acting on a Bannock man's account of gold in a mountain basin, guided the 1862 expedition that co-discovered the Boise Basin goldfield with George Grimes, one of the richest placer districts in the Northwest.
Moses Splawn was an American prospector and stockman, a member of the Splawn family of pioneers who settled in the Yakima country of Washington Territory; his younger brother Andrew Jackson Splawn became a noted cattleman and memoirist whose book Ka-mi-akin preserves much of the family story.
While mining in the Salmon River excitement of 1861-62, Splawn heard from a Bannock man of gold in a basin across the mountains to the southwest. He pursued the lead persistently, and in the summer of 1862 he and George Grimes led a small party from the Auburn and Walla Walla country into the timbered basin northeast of the Boise River. On 2 August 1862 the party found rich placer gold on what became Grimes Creek. Days later Grimes was shot dead, by Indians according to the traditional account, though versions differ, and the survivors, Splawn among them, withdrew to the settlements for supplies, returning that fall with a larger and better-armed company.
The Boise Basin rush that followed was the greatest in Idaho's history, building Idaho City and its sister camps and drawing tens of thousands of miners. Splawn himself returned to the Yakima Valley cattle country and lived out a quieter life; his birth and death dates are not consistently recorded in accessible sources, and he is remembered chiefly through his role in the discovery and his brother's memoir.