Boise is the one and only capital of Idaho, but that wasn’t always the case. Before Idaho became a state, Lewiston was the seat of government of the Idaho territory. So how did it change?
Lewiston, Idaho was an important location in the early days of western settlement, partially because it sits on the Snake and Clearwater Rivers. It was settled by gold miners, settlers, and farmers.
In 1863, Congress created the Idaho Territory (before that — the entire state was a part of the Washington Territory), and Lewiston became the seat of government.
Although it is considered a “stolen” capital by many north Idahoans, the territory capital was never actually established in Lewiston.
“When the territory of Idaho was established by Congress, March 4, 1863, the law provided that the first territorial legislature should select a permanent capital,” according to the Idaho State Historical Society (ISHS). “Originally, before the new territory was set up, the weight of population had been in the north and the principal city there was Lewiston. When the first territorial governor, William Henson Wallace, reached the territory in July, 1863, it was logical for him to establish his office in Lewiston and proclaim the organization of the territory from that town. It was also to Lewiston that he summoned the first territorial legislature in December, 1863. That first legislature in Lewiston in 1863 did not face the issue of locating a definite territorial capital. Thus all through 1864, Lewiston was the temporary seat of the territorial government, but there was no permanent capital.”

Lewiston, Idaho.
As gold dried up in north Idaho, much of the population began moving south. Gold was found in the Boise Basin in 1862. By fall of 1863 the area around Boise now had a higher population than the area around Lewiston.
“Originally, before the new territory was set up, the weight of population had been in the north and the principal city there was Lewiston,” according to ISHS. “When the first territorial governor, William Henson Wallace, reached the territory in July, 1863, it was logical for him to establish his office in Lewiston and proclaim the organization of the territory from that town. It was also to Lewiston that he summoned the first territorial legislature in December, 1863.”
There was a fight amongst citizens, with southern Idaho residents wanting the capital further south.
The Idaho Secretary of State, Clinton DeWitt Smith, named himself governor while Governor Caleb Lyon was out of state duck hunting, and brought federal troops in an attempt to steal the territorial seal and with it, the capital. According to ISHS, Lewiston moved the state seal and accompanying papers to the jail and stationed armed guards to guard them. DeWitt Smith found out and broke the lock holding the seal and accompanying documents, stole them, and arrived back in Boise.
Northern Idahoans fought it, but in 1866, the Idaho Territory’s Supreme Court upheld the new capital in south Idaho. Idaho did not become a state until 1890, and the capitol building in Boise began construction in 1905.