3 Jul 1890
On July 3, 1890, Idaho became the forty-third state of the Union. Idaho population then was 88,548. The Oregon Trail had opened in 1842, but for two decades, people merely crossed Idaho over it; virtually no one settled. In 1860, 14 years after Idaho had officially become US land through the Oregon Treaty with the United Kingdom, Mormons from Utah established Franklin, Idaho's first permanent settlement.