Idaho was first presented to Congress, by mining lobbyist George M. Willing, as a name for a new territory around Pike's Peak. He told Congress that Idaho was a Shoshone Indian word that meant "Gem of the Mountains." Indian names were popular at the time and by the end of 1860, Congress was set to name the Pike's Peak region Idaho. Just as Congress was about to bestow this name, it came to their attention the Idaho was not an Indian name, but a name made up by Mr. Willing. In reaction, Congress designated the territory Colorado instead of Idaho.

In the meantime, the word Idaho had come into common usage. One of the mining towns in Colorado Territory had been named Idaho Springs. A Colorado steamboat launched on June 9, 1860, for service between the Cascades and The Dalles, was named "Idaho." Gold was found in Nez Perce country, and these discoveries became known as the "Idaho Mines," perhaps after the steamboat used in the gold rush up the Columbia River. Though Idaho had been discarded as a name for the new territory, the name became well known from Washington D.C. to the Pacific northwest. In 1863, Congress created a new territory for the Idaho Mines and Idaho seemed like a natural.