Marshall soon entered into a partnership with Sutter for the construction of a sawmill. Marshall was to oversee the construction and operation of the mill, and would in return receive a portion of the lumber. After scouting nearby areas for a suitable location, he eventually decided upon Coloma, located roughly upstream of Sutter's Fort on the American River. He proposed his plan to Sutter, and construction began in late August. His crew consisted mainly of local Native Americans and veterans of the Mormon Battalion on their way to Salt Lake City, Utah.